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Oliver
02-10-2011, 04:03 PM
This is the third in a series of posts that are going to teach you most of what you need to know about Aquaponics. So, if you're curious about the most amazing food growing technology on the planet today, watch for this series of educational posts on Aquaponics and please, become interactive by making comments or asking questions.

In Part One, "The Process", I wrote about what Aquaponics is and why it is important to Preppers (those preparing for what is about to come down the pike), the fact that you can grow food for you and your family year round as long as your Aquaponics system is in the proper environment. I also gave a description of the biological processes involved that make Aquaponics work.

In Part Two, "System Design", I wrote about the components of a basic system.

To quickly review, I wrote about the need for a bio-filter and that it is usually combined with the grow bed to form a single Aquaponics component called the grow bed, which is the most important part of an Aquaponics system. I told you about the grow bed media, the grow bed shape, and that you need about one gallon of grow bed/bio filter volume for every gallon of fish tank volume and the reason for this ratio.

So, let's continue with the discussion on system components.

Some will argue that the standard is two gallons of grow bed container capacity to one gallon of fish tank capacity instead of the one to one ratio I mentioned in Part Two. Again, the number for expanded clay is 1:1 and for gravel about 1.5:1 gallons of grow bed container capacity to fish tank capacity. The reason for this one to one ratio limitation is that the water in the fish tank goes up and down during the grow bed's flood and drain process and too much variation in water height can stress the fish. You can use the 2:1 number only if you flood and drain some of your grow beds but not all; or if you add a sump tank to catch the water that would otherwise be returned directly to your fish tank.

The simplest Aquaponics system design has a low to the ground fish tank that is 24 to 30 inches high and grow beds that are up on tables high enough so that the water pumped up from the fish tank to the grow beds can gravity flow back into the fish tank from the bottom of the grow bed siphon. I prefer 24 inch high fish tanks so the grow beds don't need to be so high and, therefore, you don't need a step up to comfortably reach across them. This allows for at least six inches of extra siphon draw down below the grow bed thereby reducing the grow bed's drain time (more on this later).

The grow beds' siphons activate on their own timeline; but at some point, with multiple grow beds, the siphons arrive at nearly the same schedule. Like two or more metronomes, occasionally they all sync up and drain at the same time filling the fish tank to capacity and then they simultaneously pump water into and filling all the grow beds. With a two to one grow bed to fish tank ratio, the extra water required to fill the grow beds leaves the fish tank with a dangerously low amount of water, which will stress the fish. With a one to one grow bed to fish tank volume ratio, the water level in the fish tank won't go so low as to stress the fish. So, one to one is the number you want to aim at in your Aquaponics system design.

Some will argue that one way to avoid this water level in the fish tank problem created by increasing grow bed volume is to add a sump tank (mentioned above) that catches the drained water from the grow beds. The water is then pumped back to the fish tank from the sump tank after it's water reaches a certain level by way of activating a float switch connected to a submersible pump in the sump tank. This allows the sump tank to absorb the intermittent water flowing into it and helps keep the fish tank from experiencing major swings in water level during grow bed siphoning.

For a short fish tank that sits on the ground, this requires an extra pump (in addition to the one in the fish tank) and a float valve switch (mentioned above) in the sump tank, which adds extra parts, cost and potential points of failure. Turning a pump motor on and off repeatedly shortens its life, and, if either the pump motor or float valve switch were to fail (and eventually one or the other will fail), you will have water all over the place, a fish tank void of water and dead fish. In my opinion, this is not a good design. You might as well increase the size of your fish tank and keep the same number of fish, thereby saving yourself the cost of the sump tank, pump and float switch, along with its complexity and poor reliability.

Other system designs raise the fish tank or have a tall fish tank, like a tall IBC tank with its top cut off, that overflows through a pipe into grow beds that are positioned at a lower level. The water returns to a low siting sump tank from the grow bed siphons and directly from the fish tank overflow where a continuously running submersible pump is pumping water from the sump tank into the fish tank. Additional plumbing is used to be able to divert the water as needed for system maintenance without turning off the complete system and to adjust the flow of water into the grow beds. It is an elegant design because it adds only minor complexity and cost to building your system while using a single continuously running pump, and it works well. It is very important that a float valve be added to the sump tank in order to assure that there is enough water in the system; for evaporation will reduce the water level in the fish tank to a level where it won't overflow, thereby starving the pump in the sump tank.

The problem I have with this fish tank overflow design is that, even though the overflow water is gathered from the bottom of the fish tank, it is not run through a pump prior to entering the grow beds. This allows the fish waste solids to go directly into the grow beds in their sheathed form. The solids I have witnessed and watched on my fish cam are wrapped in a clear sheath, which appears to be the slim component of the worm like solid. By sending the solids through a submersible pump they get macerated, thereby breaking them into smaller components, which allows for the heterotrophic bacteria to do a faster job of mineralization. To leave them in the sheathed form may allow them to accumulate in the grow beds often on top of the media.

The simplest of systems has a submersible pump in a low fish tank that pumps ample water under pressure to the grow beds. The water can be controlled by valves at the grow beds in order to regulate their fill rate while providing some additional water under pressure to be jetted back into the fish tank in a high velocity stream for added aeration. This extra pump pressure allows for purging of the lines to the grow beds by fully opening the grow bed control valves individually for a short period of time. This needs to be done periodically because the fish waste solids are heavier than water and the slow flow up to the grow beds doesn't allow for all of the solids to make it into them. This slow upward flow causes some accumulation of solids in the plumbing, which the purging alleviates.

The auto siphons return the water to the fish tank from the grow beds by gravity. This is accomplished by using a line connected from the bottom of the siphons below the grow beds to the fish tank above the water level. The grow beds are high enough without being too high, and the fish tank is low enough to allow for a good flow return from the siphons. This pretty much describes the systems I have designed (minus the aeration) and am currently using, which are elegant in their simplicity and very cost effective. Again, to be clear, I have borrowed significantly from others tried and tested work.

Grow beds can be made of wood with plastic liners, but fitting them with the needed bulkhead fittings that don't leak may prove to be a challenge. However, it is successively done all the time. The bulkhead fittings in the grow bed bottoms are necessary and are part of the siphons. Some Aquaponics system builders use flush valves instead of siphons and slowly filled plastic water bottles to trigger the flush valves. I am told they work quite well and are very adjustable while adding minimal moving parts and complexity even though they are not very aesthetically appealing.

Hydroponic reservoirs make good grow beds (at least the twelve inch deep square black ones do). These seventy gallon, ten plus square foot (one square meter) reservoirs are what I have used in our systems, and they are very sturdy. These reservoirs do need bottom support when used as elevated grow bed containers because they are made to sit on the floor. The rectangular white ones are very flimsy, somewhat pricey; and I wouldn't recommend them, even though they have a nice form factor of thirty inches wide. They can be used with some side and bottom support.

I recommend using animal stock tanks as fish tanks. They are twenty four inches tall and, depending on the brand, are very well made from USDA approved polyethylene with UV inhibitors. You don't want to have a black fish tank because it limits the light in the tank making it hard to see the fish. Many fish species do better with more light.

As for submersible pumps, I recommend magnetic drive (mag-drive) pumps because the motor is in its own sealed compartment and should never leak any oil out into the fish tank water, which would be really bad for the fish. Good ones are relatively inexpensive and have a three year warranty. The pump should be capable of turning over the total gallons in the fish tank about every thirty minutes at six feet of head pressure minimum. Be careful of advertised flow rates at zero head pressure because that doesn't tell you what you need to know for your system (more on this below).

In sizing your pump, make sure you have enough flow to fill all of your grow beds at least four times and hour. For example, let's say you have a 120 gallon fish tank and two 70 gallon hydroponic reservoirs as grow bed containers for a total of 140 gallons of grow bed capacity. The water in the grow bed will only be filled up to the 60 gallon mark, for a total of 120 gallons for two grow beds. The grow bed media will displace half of that so now we are looking at about 60 gallons of water total in the two grow beds. Not all of the water will drain, so let's say about a total of 50 gallons drains out before syphon break. We replace that four times an hour so we need 4 X 50 = 200 gallons per hour just to fill the grow beds. We need another 20% to jet back into the fish tank for additional aeration, which is 40 gallons per hour. The total water is 200 + 40 = 240 gallons per hour at 6 feet head pressure. This works out to be twice the fish tank volume every hour.

Pumps come in discrete sizes, so we use a 1000 GPH at 6 feet of head pressure pump. The rule is to always over size your pump in case you wish to add other components to your system later that require water under pressure, like vertical grow towers or an elevated small brooding tank, both of which can gravity flow/overflow back into your main fish tank.

You should never have any metal in your system or plumbing, including the fish tank, metal grow bed containers without liners, valves, especially copper, zinc or brass because they will leach toxic metal into the water and kill your fish. Just stay completely away from any metal coming into contact with your system water with the exception of iron or stainless steel.

We use diaphragm type air pumps that require the diaphragms to be replaced after about one year of continuous use, but they are very inexpensive and easily changed. Air pumps are notoriously inefficient. They produce lots of heat and move little air, but they are absolutely essential for your Aquaponics system. You will need a pump rated at about 7 GPH of air for each gallon of fish tank capacity. With a change from 5 GPH to 8 GHP of aeration per gallon of fish tank water (a 50% increase), we saw a better than 1.5 ppm increase in DO (dissolved oxygen).

The best way I have found to put air into the tank is through cylindrical air stones. Even though they have relatively large air bubbles, they don't clog up as much as the finer bubble diffusers.

Our DO regularly measures between 6 and 7 ppm depending on water temperature. A study made with tilapia and varying amounts of dissolved oxygen (DO) in the water showed a doubling of growth rate from a DO of below 3 ppm to a DO above 6 ppm.

Air pumps need to be run 24/7, to do otherwise is to kill fish. After all, how long would you last without air?

This, and the previous post, describe one type of Aquaponics system with some variation; but, by no means, covers all of them. I've also shared some information about the design of the systems we have up and running. For those of you who will be building your own systems, we're sharing these details about how to build them yourself because we really believe food shortages are coming; and we want to help as many people as possible get prepared. So now you can buy the parts from various vendors and build your own custom systems. As long as you follow the above suggestions, you will have a system that has the potential to work well and produce food because it is properly designed.

Oliver

Part Four will be about System Start Up.

kyrocketscientist
06-09-2011, 03:38 PM
Oliver, I really appreciate all the info you are posting, free of charge. I have been searching the inter-net for 2 weeks trying to get info on aquaponics, and everywhere I go, people have their hand out.
I have learned more in the last hour from you than I have in the last 2 weeks. I have watched all those post on U-tube from folks that seem to be high on something, that profess to have the solution to a cheap DIY for an aquaponic system, but it is a wast of time. I am in the planning stage, but I am getting close. Thank you very much...John

urbanfarmer
06-09-2011, 05:16 PM
Welcome kyrocketscientist!

Oliver
06-09-2011, 08:42 PM
Oliver, I really appreciate all the info you are posting, free of charge. I have been searching the inter-net for 2 weeks trying to get info on aquaponics, and everywhere I go, people have their hand out.
I have learned more in the last hour from you than I have in the last 2 weeks. I have watched all those post on U-tube from folks that seem to be high on something, that profess to have the solution to a cheap DIY for an aquaponic system, but it is a wast of time. I am in the planning stage, but I am getting close. Thank you very much...John
John,

Thank you for the comment. There are a number of members of this forum that know a lot about different ways to make an Aquaponics system work and work well. So, please ask lots of questions here. You may receive conflicting answers at times but that is because Aquaponics is still in its infancy and we are all still learning.

Welcome to the DIY forum.

Oliver

mbrown
06-15-2011, 07:04 AM
I have a question, what about a bio filter? is it necessary and where would it be located in the system? I added one by the advice of a member on here and I'm not sure of the purpose. Just looking for conformation. Thanks.

Oliver
06-15-2011, 10:13 AM
I have a question, what about a bio filter? is it necessary and where would it be located in the system? I added one by the advice of a member on here and I'm not sure of the purpose. Just looking for conformation. Thanks.
I suggest your read this series of articles titled "Aquaponics 101", starting with part one. I think your question will be answered along with, perhaps, other as yet unasked questions.

Oliver

keith_r
06-15-2011, 10:20 AM
in most backyard systems, the biofilter is the growbed, this is where most of the bacteria live that perform the process of breaking down your ammonia to nitrites, and then to nitrates
add some red wiggler worms in your growbeds to assist with breaking down solids..
easy peasy HA

mbrown
06-15-2011, 07:49 PM
in most backyard systems, the biofilter is the growbed, this is where most of the bacteria live that perform the process of breaking down your ammonia to nitrites, and then to nitrates
add some red wiggler worms in your growbeds to assist with breaking down solids..
easy peasy HA

Then is the bio filter necessary? My fish seem to be doing well, now, I did have a few die for what ever reason. Could have been me trying to change pH and alkalinity at the same time. I am going to try and add the worms and skip the bio filter, add more aeration and continue to add the liquid seaweed with chelated iron. Also I will add 12 more fish, this will give me 28 commit goldfish in a 300 gallon tank that works on a overflow system so the level only changes 4" total drop.

Onthefly
06-26-2011, 12:20 PM
@Oliver or?
You are using a low profile FT to reduce head, how many gallons is your FT('s), what is the foot print? I am still in planning stages and leaning towards an IBC for cost reasons and also for getting more gallons thus more fish. I can however partially bury to get to a desired height, or should I bite the bullet and purchase a tank designed for this? From what I've read a 275 Gallon system should be the minimum to reduce chemistry fluctuations.

I'm leaning towards drain and fill but not at all against constant flow, would I be correct in stating that the constant flow method will use more energy? Also, you are not using a sump tank to catch solids but are using the additional flow your pump is capable of to clean out the solids in plumbing, correct? I'm assuming you do this after a harvest and with an empty bed, correct? I know most pumps do require some back pressure but can you create enough on the pump w/out damaging pump or are you diverting some back to FT?

I want a big enough system to start for reasons stated above but I would think if one was planning on having a larger system you would not want several smaller systems thus creating more of a plumbing nightmare. I really would like to have 1k or 1.5k total FT gallons but would this be wise for a beginner?

Yours or anyone's thoughts please, thanks.

JCO
06-27-2011, 06:41 PM
I don't know what has happened to Oliver, he seems to have disappeared on us, however in the past I have built my FT outside by building a frame work of 4"x4" post 3' or so in the dirt and about 30" above ground. Then I use 1"x6"s to build the sides above ground. Then I dig out the interior into the dirt the desired dept going from shallow to deep to encourage the poo to the deep end to be pumped out. I then mold and smooth the dirt interior to suit my taste then line the dirt portion with used carpet foam padding. The I line the entire interior with 10 mil black plastic (available at Home Depot 100'x20' for about $200.) (You will have plenty left over for lining the the grow beds for raft systems.) I put 1"x6" cap rails on the top all the way around to make it presentable and to hide the plastic that is tacked to the top of the top board.

As for how big to go...I would go as big as you can afford...regardless of how many grow beds you have gallon wise as long as you have the bio-filter power to convert the ammonia and nitrites to nitrates, that's the major issue. With a big FT, you can always expand your grow beds as you please, but if you have a small FT, you will have to increase it's size in order to be able to handle more GBs. If you have more FT than recommended for the GBs and the plants aren't using all the nitrates, no problem...I have found nitrates to be relatively harmless to the fish (I have never had a problem with nitrates being too high myself) but you have to get rid of the ammonia and nitrites. They are the killers.

I hope this helps. :mrgreen:

Onthefly
06-27-2011, 07:04 PM
Thank you JCO, do have any pics of your system on here? Sounds interesting although I would need a backhoe to dig where I'm at, hard clay (gooey when wet) and rock. I've dug several holes for posts with a post hole digger and if I get lucky I can dig down 3' in an hour, if unlucky a whole day it seems. I can always rent a backhoe so thats not a huge problem. So all your GB's are raft? What advantages do you see in your system vs others?

I'm all ears, thanks.

stucco
06-28-2011, 02:31 AM
I've dug several holes for posts with a post hole digger and if I get lucky I can dig down 3' in an hour, if unlucky a whole day it seems.




My ground is pretty soft here but every now and then I hit some hard pack clay. I found that a pressure washer with a rotating tip works well for the post holes.

JCO
06-28-2011, 06:30 PM
Sorry, no pics at this time and yes, my GBs are raft systems... :mrgreen:

Onthefly
06-28-2011, 08:13 PM
Hmm interesting Stucco, will give that some thought. May work well until we hit rock anyway.

Thanks

Oliver
06-30-2011, 09:35 PM
@Oliver or?
You are using a low profile FT to reduce head, how many gallons is your FT('s), what is the foot print? I am still in planning stages and leaning towards an IBC for cost reasons and also for getting more gallons thus more fish. I can however partially bury to get to a desired height, or should I bite the bullet and purchase a tank designed for this? From what I've read a 275 Gallon system should be the minimum to reduce chemistry fluctuations.

I'm leaning towards drain and fill but not at all against constant flow, would I be correct in stating that the constant flow method will use more energy? Also, you are not using a sump tank to catch solids but are using the additional flow your pump is capable of to clean out the solids in plumbing, correct? I'm assuming you do this after a harvest and with an empty bed, correct? I know most pumps do require some back pressure but can you create enough on the pump w/out damaging pump or are you diverting some back to FT?

I want a big enough system to start for reasons stated above but I would think if one was planning on having a larger system you would not want several smaller systems thus creating more of a plumbing nightmare. I really would like to have 1k or 1.5k total FT gallons but would this be wise for a beginner?

Yours or anyone's thoughts please, thanks.
I'm back.

As stated in AP101, I'm using a low profile fish tank so I can keep the grow beds low enough to reach across without having to have a step up.

My fish tanks are 4 foot diameter, 2 foot high 120 gallon stock tanks.

I challenge the idea that an aquaponics system has to be a minimum number of gallons for biological stability. It has more to do with the fish to water ratios, regardless of the size. This assumes a constant system temperature.

The system's temperature stability is another matter. It has to do with the volume of water to the surface area of the container (fish tank) plus the surface area of the top of the water in the fish tank. Add to that the surface area of the grow beds (all 6 sides) and the water contained therein. Then consider the amount of insulation, if any, surrounding these components as well as the varying air temperature where your system is located and you have the thermal stability.

The temperature stability affects the biological stability, however. So, the larger system may have a better overall stability due to the larger thermal mass to surface area ratio.

The extra pump capacity is used to rapidly move the fish tank water through the plumbing to the grow beds in order to clean out the plumbing. This is necessary as the normal flow from the fish tank to the grow beds is very slow and the fish waste solids tend to accumulate in the plumbing. This is accomplished by fully opening the control valve in the line to the grow bed and allowing the full force of the pump to rapidly move the water through the line for a period of about 30 seconds, at least once a week. The water coming out during that time will be very brown. When it clears, then reduce the flow to the proper amount for your flood and drain cycle timing.

The above procedure has nothing to do with harvest. Depending on the amount of accumulated roots in the grow bed, they can be cleaned out after a complete grow bed harvest. Quite often, however, the grow bed is planted in sections and is usually in different states of growth. This is more the case with a larger grow bed.

Another reason for using an in-fishtank pump is that the solid fish waste gets macerated as it passes through it. In this process the surface area of the waste is increased. This allows for more heterotrophic bacteria interaction, thereby reducing the amount of time it takes for the solid waste to be mineralized.

A good quality pump, such as a mag drive one, should be able run continuously with the output completely shut off without it being damaged. The energy used is the product of pressure times flow, plus some inefficiencies. I have yet to test this assumption, so when I do make these tests I may have more to say about this statement. I plan on measuring the electrical power used by the pump while varying the back pressure by adjusting a valve on the pump's output.

The flood and drain method I wrote about uses a constant flow of fish tank water coming into the grow beds, the pump's energy use does not change if they are flood and drain or continuously flooded. We can change between the two methods by breaking the seal on the rubber cap we use on top of the syphon shroud.

The macerated fish solids go to the grow bed/bio-filters where they break down over time. With deep grow beds (12 inches) they break down before they reach the bottom and begin to accumulate.

The purpose of a sump tank is not to accumulate fish waste solids, but to collect the water returning from the grow beds to eventually to be returned to the fish tank. A sump is only necessary if the grow bed bottoms are lower than the top of the fish tank.

I would suggest getting some experience on a smaller system so when you kill some of your fish due to inexperience, they will be fewer in number.

Oliver

"To measure is to know"

davidstcldfl
07-01-2011, 04:55 AM
Hi Oliver ... :D

Oliver
07-14-2011, 11:42 AM
I have just added the following paragraph to the original post above. It follows the paragraph on using a tall fish tank and allowing the water to overflow into the grow beds.

"The problem I have with this fish tank overflow design is that, even though the overflow water is gathered from the bottom of the fish tank, it is not run through a pump prior to entering the grow beds. This allows the fish waste solids to go directly into the grow beds in their sheathed form. The solids I have witnessed and watched on my fish cam are wrapped in a clear sheath, which appears to be the slim component of the worm like solid. By sending the solids through a submersible pump they get macerated, thereby breaking them into smaller components, which allows for the heterotrophic bacteria to do a faster job of mineralization. To leave them in the sheathed form may allow them to accumulate in the grow beds."

Oliver

kyrocketscientist
07-15-2011, 06:15 AM
More advice needed.
I'm in the planning stage. I'm thinking a 150 gal stock tank for the fish , 2 each 50 gal stock tanks for the grow tank. I'm reading all the problems newbies are having with the bell sipon, and it looks to me like the loop syphen would be the sure fired way to go. What as I missing? Also, I could use advice on the type and amount of fish to use. I know, me not knowing what I am doing, I will need to have fish that can stand big swings in water temp, as my blue prints in my head have not addressed how to control the water temp. I know the best way to controll tempature swings would be to use a larger FT. I could go to a 200 gal and maybe put in a float grow pad in the top. I have no idea of amount and size of fish I need to provide the nitrates for 2 grow tanks that are 50 gals each and 12 in deep. I have read that it will take awhile before I can plants the blooming plants (tomato and pepper), but that is what this passive green house project is all about. TOMATOES AND PEPERS IN THE WINTER, yehi.....John

keith_r
07-15-2011, 06:25 AM
a "basic" rule of thumb is 25lbs grown out size (not starting size) fish to 100gallons of filtration.. so you've got 100gallons of gb, 25 fish that you expect to grow to about 1lb would be right at the edge
what kind of fish do you plan on using?
with that name i'd have to say you are probably in ky? look for a local species like bluegill/perch/catfish, unless you plan on heating the water for tilapia, not sure about ky's laws and tilapia though

Oliver
07-15-2011, 10:24 AM
kyrocketscientist

I see that you are posting this under one of the AP 101 segments. I suggest that you read all of the segments, for I believe that most of the questions you are asking are answered in the articles.

It would be helpful if you would go to your profile and update your location. This would give us an idea about what kind of temperature swing you are having and, perhaps, the kinds of fish you can raise in your area.

Also, due to your temperature swing problems, it would also be helpful to know what kind of climate protection you have or plan on having for your system.

As suggested in AP 101, it is not a good idea to grow flowering plants in your grow beds until your system is mature and you have a high fish density.

Oliver

kyrocketscientist
07-15-2011, 10:46 AM
I knew I had read not to expect to raise flowering plants for a while, now I know where I read that. I am in Ky just across the river from Evansville In. I plan to have a pasively heated leanto type greenhouse with one exhaust fan. I have 3 double pane house windows that I can raise with the fan on for cooling.. My back wall will be 2x6 with 5 1/2 inch insilation, and the same with the front and side kick wall. I'm planning on digging down 3 ft and placing the 4" sewer pipe and covering them with 4" limestone, placing the sewer pipe one ft on center verticly and 2' on center horazonily (I may be a rocketscientist, but I cant spell), and use some 12 volt fan to circulate the air powered with a solar cell. I have located the stock tanks at Rual King and I am just waiting on grandpa's day where every thing is 10% off to purchase them. I am probably 2 weeks from starting construction. I have priced hydroton and it is quite expensive, so I may go with river run gravel, as the Ohio river is right here and I hope rather cheap. I value your advice and thank you in advance....John

disco
07-15-2011, 11:50 PM
I have found this site to be better on pricing than many others. Not sure of shipping costs, haven't ordered or built anything yet. :)
http://www.hydrowholesale.com/

kyrocketscientist
07-21-2011, 06:54 AM
Oliver or anyone
It was stated in part three that I should use a diaphragm air pump capable of producing 7.5 GPH for each gallon of FT. With a 150 gal FT, that would be just over 1000 GPH. I cant find one. To get into the 1000 GPH range, they come in a piston pump, and I was cautioned by a suppler that they were very noisy. HELP. Also Oliver said that two 4 ft Aquafuse lines were added to each GB, but there was no mention of what, or how many or how much to put in the FT. HELP.....John

rfeiller
07-21-2011, 07:35 AM
kyrocketscientist
if you go to http://www.hydrofarm.com look up air pumps the activeaqua AAPA3.2L 3.2liters per minute is 2 watts and that is plenty for what you have for basic aeration.
i personally use the AAPA45L 45liters per minute at 20watts it comes with a 6-valve outlet manifold. i run two air devices each on 2-50gal AND 1-90gal aquariums. i use one of those pumps with 6 airstones for a 1000gal FT.
doing conversions from liters to gals to cu ft can really get confusing; usually the piston type pumps are rated in cu. ft. per min. then there are the turbos that can handle several hundred outlets. there can be some confusion, in that most air pumps are rated in per minute, not per hour.
just basic aeration you can cover for about $10. you can go up from there depending on what you are trying to accomplish. i have a model AAPA110L pump on a 10" diffuser plate in a 2500 gal KOI pond i had built it for the 1000gal FT and the fish did not care for that much turbulance. :)

kyrocketscientist
07-21-2011, 07:43 AM
Thanks rfeiller, I'll try them. One supplyer on Ebay, who did the conversion said I needed a 70 liter pump to get 1000 GPH

rfeiller
07-21-2011, 07:44 AM
that will pretty much blow your fish out of the water in a 150 gal aquarium

kyrocketscientist
07-21-2011, 07:57 AM
rfeiller again. The pump you use, ebay says it is a piston pump and very noisy. What do you think?

rfeiller
07-21-2011, 08:48 AM
the pumps that i was referring too for you were the diaphram pumps. the pumps i use do make a noise, which i am not concerned about.
the ActiveAqua diaphram pumps go up to 25liters per minute, those are quite. i am confused about the quantitiy of air you are going for to use in a single small 150 gal tank.
if you have a good KOI store near you they, at least in my area carry diaphram pumps, at least very quiet pumps that have a much larger capacity. they can run well over $100-$200.
there is a big difference in performance between what you can buy at Petco and these pumps. how they handle back pressure is the biggie. good luck.

Shas
12-07-2011, 11:27 AM
"The reason for this one to one ratio limitation is that (?????) the simplest Aquaponics design has a low to the ground fish tank..."

Oliver, it looks to me like a paragraph was lost here.
The topic seems to have changed where I put the question marks.
Or is it just me?

Thanks

Oliver
12-07-2011, 09:53 PM
It does appear as though I digressed. I could go back and rewrite that paragraph for clarity. When I get a little time earlier in the day I will do that.

Thanks for pointing that out.

Oliver

Shas
12-07-2011, 11:04 PM
I'm not stressed, Oliver,
I just want to hear the end of that sentence!
"The reason for this one to one ratio limitation is that..."
I'm sitting on the edge of my seat here!

Thanks again for an excellent presentation of information.
Concise, articulate, authoritative, accessible. generous, relevant and interesting.
May your tribe increase!
Would that more of my profs had been like you!

Shas

Oliver
12-08-2011, 11:14 AM
Ok, I moved the "reason for a one to one ratio" sentence into the previous paragraph. I hope that helps explain the concept.

Oliver

Shas
12-08-2011, 01:11 PM
"The reason for this one to one ratio limitation is that the water in the fish tank goes up and down during the grow bed's flood and drain process and too much variation in water hight can stress the fish"

Got it.
Thanks.

newimaging
12-25-2011, 09:23 PM
I have built my FT outside by building a frame work of 4"x4" post 3' or so in the dirt and about 30" above ground. Then I use 1"x6"s to build the sides above ground. Then I dig out the interior into the dirt the desired dept going from shallow to deep to encourage the poo to the deep end to be pumped out.
I hope this helps. :mrgreen:

JCO, do you have any pictures of the construction from that kind of tank or grow bed. I would be interested. Also, do you require heating for your tank?

Shas
01-08-2012, 11:06 PM
Oliver, thanks again for this excellent treatise.
I'm learning a lot from you.
I'd like to ask about this statement:


You should never have any metal in your system or plumbing, including the fish tank, metal grow bed containers without liners, valves, especially copper, zinc or brass because they will leach toxic metal into the water and kill your fish. Just stay completely away from any metal coming into contact with your system water with the exception of iron or stainless steel..

I have heard this warning for forty years,
and have passed it along many times.
But somehow my own experience doesn't seem to support it.

I know that copper is the traditional biocide in marine paints,
and it seems to do a decent job
at discouraging both plants and invertebrates from growing
on boat bottoms and submarine structures.
Yet humans have been drinking from copper pipes
and cups and kettles since the Bronze Age.
And I'm guessing that very few of us are filling our fish tanks
with water that has NOT travelled in copper pipes.

When I was raising angel fish commercially back in the 1980s
I found that the lead water pipes in my old house
interfered with the development of both eggs and fry.
After a house fire (arson, unrelated to the fish business)
I replaced all my pipes with copper
and my cichlids seemed happy and healthy,
breeding freely and with high hatching, survival, and growth rates.
I was doing some selective breeding
and had probably up to twelve generations of breeders,
with no decrease in health, growth, or survival rates,
so there didn't seem to be any cumulative ill effects from the copper pipes.

So what is the real-life effect on fish and gardens
of heating and delivering water with copper pipes?
Are we perpetuating a myth?
If the risks of low-level Cu-contamination are purely hypothetical,
we can save a lot of cost and effort
by simply using domestic water heaters directly.

Can you educate me on this issue?
Thanks.

davidstcldfl
01-09-2012, 04:46 AM
Just my 2 cents Shas...I think it has to do with the water 'in' the system having a lower PH. The system's water in theory, would break down the metals faster, then regular drinking water.
Plus, in AP, generally we aren't doing 'water changes'....so the metals have a better chance to accumulate.


Just a side note....in a domestic water system with copper pipe....most leaks occur just after fittings, especially 90's. The extra turbulence and the minerals in the water, actually wear right through the pipe's wall.

foodchain
01-09-2012, 05:32 AM
not just the minerals. Municipal water is full of dirt, crud, and metal chunks. Pull off the screen of your faucet and see the build up.
I used to do the potable water tower inspections while they are full of your drinking water...there's inches of sediment in each one of those tanks. Kinda gross that you often find critters, etc floating in them too. Enough to cure you from drinking tap water.

bsfman
01-09-2012, 07:38 AM
Yet humans have been drinking from copper pipes
and cups and kettles since the Bronze Age.
And I'm guessing that very few of us are filling our fish tanks
with water that has NOT travelled in copper pipes.


I've wondered about this too, Shas. Without question, copper is toxic to fish in sufficient concentration, but is contact with copper plumbing apt to leach toxic levels of copper ions into the water? Perhaps so, perhaps not. Grain mashes used in the production of beer and liquor are typically conducted at pH levels in the 5 to 5.5 range - much more acidic than our AP system water. Then the liquid is boiled in copper kettles and in the case of liquor, condensed in copper pipes. You would think, if copper is indeed this soluable, that toxic levels would build up in beer and liquor drinkers.

It would be an interesting experiment to recirculate water in a small aquarium using copper pipe plumbing along with an identical control system set up using PVC plumbing, then test the water after a period of time for copper. I wouldn't know how to even begin testing water for copper, but maybe we can talk Urban Farmer into trying this out for us. Given his penchant for scientific analysis, I bet such an endeavor would be right up his alley! :P

foodchain
01-09-2012, 10:35 AM
Wouldn't a heavy metals test achieve this? Readily available testing kits for it. As well as agriculture, and soil/water testing facilities. I looked into buying a private lake, 113 acres and a hydrologically connected system of ponds for fingerlings. And had to look into these kinds of testings.

Oliver
01-09-2012, 08:47 PM
Oliver, thanks again for this excellent treatise.
I'm learning a lot from you.
I'd like to ask about this statement:


You should never have any metal in your system or plumbing, including the fish tank, metal grow bed containers without liners, valves, especially copper, zinc or brass because they will leach toxic metal into the water and kill your fish. Just stay completely away from any metal coming into contact with your system water with the exception of iron or stainless steel..

I have heard this warning for forty years,
and have passed it along many times.
But somehow my own experience doesn't seem to support it.

I know that copper is the traditional biocide in marine paints,
and it seems to do a decent job
at discouraging both plants and invertebrates from growing
on boat bottoms and submarine structures.
Yet humans have been drinking from copper pipes
and cups and kettles since the Bronze Age.
And I'm guessing that very few of us are filling our fish tanks
with water that has NOT travelled in copper pipes.

When I was raising angel fish commercially back in the 1980s
I found that the lead water pipes in my old house
interfered with the development of both eggs and fry.
After a house fire (arson, unrelated to the fish business)
I replaced all my pipes with copper
and my cichlids seemed happy and healthy,
breeding freely and with high hatching, survival, and growth rates.
I was doing some selective breeding
and had probably up to twelve generations of breeders,
with no decrease in health, growth, or survival rates,
so there didn't seem to be any cumulative ill effects from the copper pipes.

So what is the real-life effect on fish and gardens
of heating and delivering water with copper pipes?
Are we perpetuating a myth?
If the risks of low-level Cu-contamination are purely hypothetical,
we can save a lot of cost and effort
by simply using domestic water heaters directly.

Can you educate me on this issue?
Thanks.

First, thank you.

Regarding the metal pipe statement, if you have copper pipes in your house and say you have 100 feet that all the fish tank water passes through one time before reaching its destination, we can call that 100 X 1 = 100

Now, let's say you have 10 feet of copper pipe in your aquaponics system and you recirculate all of the water through that 10 feet of copper pipe twice an hour, that's 10 X 2 = 20

Lets run the system for a whole day, 24 hours, and we now have 48 circulations of all the system water through that 10 feet of copper pipe, that's 10 X 48 = 480

We continue to run the system for a whole year recirculating the water through that 10 feet of copper pipe which gives us 480 X 365 = 17,520.

Now compare the original 100 from the water coming into your home through copper pipe to the 17,520 after a year of recirculation through 10 feet of copper pipe in your aquaponics system.

How much copper is now in the water from the copper pipes in your aquaponics system? I do not know, but it will be more than if you didn't use the copper pipe to begin with.

One can also make the same argument for PVC. Another, "I do not know", at this time.

As foodchain suggests, to measure is to know.

It would be of interest to me, and I suppose some of the aquaponics community, to know the answers to these questions; and we will. As we continue to push for more knowledge by asking these questions, someone will write a grant proposal or otherwise self fund the study that will eventually reveal these answers.

Oliver

Shas
01-09-2012, 11:37 PM
How much copper is now in the water from the copper pipes in your aquaponics system? I do not know, but it will be more than if you didn't use the copper pipe to begin with.

Literal LOL!
Your logic is irrefutable, Oliver :=)

I do hope someone with the interest and resources will do this experiment.
The results would interest an awful lot of people, I think,
and potentially save many fish by supporting the "common knowledge"
or save a lot of money and head-scratching
by freeing us to use copper with confidence.

davidstcldfl's comment on pH (and bsfman's counterpoint)
suggest an important variable to be examined as well.

Foodchain, I am fortunate enough to take my water from a creek
which originates in a glacier just above my property.
When I was a youngster, a local murder was solved
when the remains were discovered in the municipal water tank.
By that time there wasn't much left but clothes and bones,
but the local bottled water industry did a booming business for a while...

foodchain
01-10-2012, 05:32 AM
You know, there's just some jobs I wish I had never done. Potable water tanks is one of them.
Nasty things. Water treatment plants....you know the big Sh**tanks were more tolerable. At least I know going in what they were.

The problem with the experiment idea, is that there are infinent variables. For instance, PH, ph levels will play a role in how much copper is dissolved. Temp plays a role in how fast/slow the PH will absorb it too. Now factor in salt, etc. To get a trully accurate experiment you would have to find a way to isolate and stabilize each variable or otherwise neutralize it from the equation.
Otherwise you would end up with results for your data....

But not clearly understand what got you there. I have been there, done that and it leaves me looking foolish when I try to explain to someone how to copy the project, and they can't duplicate the same results.

Shas
01-10-2012, 10:16 AM
You know, there's just some jobs I wish I had never done.

Ain't that the truth.
I was a pastor for many years,
and working behind the scenes in the church
was similar to working behind the scenes
in the potable water or processed meats industries...



The problem with the experiment idea, is that there are infinent variables.

Not really.
At least, not within the parameters relevant to aquaculture/aquaponics.
The pH need only vary from, say, 6.0 to 8.0
and the temperature from maybe 16 to 30 Celsius.
If we use the extremes and median values
*ie, pH of 6.0, 7.0, and 8.0 and temps of 16, 23, and 30)
that gives us nine iterations to examine.
Even including water hardness would only triple the numbers,
which would be cumbersome but quite do-able.



and they can't duplicate the same results.

That's the scientific method in action.
If it can't be replicated, it ain't true.

foodchain
01-10-2012, 01:45 PM
Absolutely true. So who wants to set up 9 identical tanks, idealy in the same room to eliminate any unmeasurable variances that are common in aquaculture and reef aquaria. And present the results?
While I have the tanks, or at least some of them....I don't have the space or time.