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Oliver
02-09-2011, 02:53 PM
This is the second 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.

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).

To quickly review, Aquaponics combines the raising of fish and using the fish waste as plant nutrients so you can grow vegetables. This is done year round and can provide food fish and veggies for your family.

The process includes the breakdown of fish waste into plant nutrients, the uptake of these nutrients by the plants being grown in separate grow beds and the cleaning of the water to be returned to the fish tank and reused in an endless loop. This is all done in a continuous flow recirculating aquaculture system called Aquaponics.

I'm now going to focus on a particular Aquaponics system type and its design, but I'll also be referring to other designs. As mentioned in Part One, the fish tank and grow beds are separate entities. This precludes growing the majority of your vegetables directly in the fish tank. However, some green leafy plants like lettuce can be grown on rafts floating in the fish tank as long as the particular fish being raised don't eat the plant roots. However, this is generally not done.

As I also mentioned in Part One, there is a need for a bio-filter, which is a part of the system; and it is filled with a media that contains lots of surface area on which the bacteria live. Most Aquaponics farmers (I'm talking about home and backyard farmers here) choose to combine their grow beds and their bio-filters into a single unit. This simplifies the design and construction of their Aquaponics system in addition to saving cost and space. It is this combined system I will be focusing on here.

The combined grow bed/bio-filter containers (from here on referred to as a grow beds) need to have enough volume to contain ample material with enough surface area to support the number of fish (by total weight) in the fish tank. They also must provide enough planting area to support the optimum amount of plants needed to uptake the nutrients without depleting the system of these nutrients, thereby causing poor plant growth. Seems complicated; but, fortunately, many have gone before and have worked this all out. We can build on their shoulders.

Grow beds are generally filled with media, either expanded clay or smooth river stones (gravel), in order to give the needed surface area on which the bacteria thrive, while simultaneously holding the plants in place. The grow bed is filled with the media to a level near the top of the grow bed container, and the fish tank water is pumped into the grow bed filling it to a maximum level that is one inch below the top of the grow bed media. This one inch barrier is to prevent the top of the grow bed media from becoming and staying wet, thereby preventing algae growth on the top of the media. This barrier also helps prevent the bottom leaves of plants in the grow bed from becoming wet and moldy.

The optimum grow bed container depth is about twelve inches. This will allow for at least eleven inches of media and ten inches of fish tank water to be placed in it, which is enough to provide for bacteria growth as well as providing ample depth for anything you wish to grow. It will also allow for some accumulation of fish solids in the bottom of the grow bed and give them time to break down before they over accumulate. Grow bed containers deeper than 12 inches are more costly to fill with media, heavier and transfer more water back to the fish tank (more on this later). Generally they are unnecessary, unless you're using gravel as a grow bed media. Then, the extra depth can be beneficial (more on this later, also). Grow bed containers less than twelve inches deep cause your planting area to grow bed volume ratio to be less than ideal, thus creating more planting area than the bio-filter volume can support (depending on what type of plants you have in the grow bed). This twelve inch number is not cast in stone; but if you build a system using it, it will work. If you use other depths, especially less, then you are on your own.

The size of the grow bed can be whatever you wish; but understand that if you go over 30 inches in width, you will have difficulty reaching across it. For wider grow beds, you will need to have plenty of walk around room to get to two opposite sides. Forty eight inches is probably the maximum width you should be considering. The length is not as important as the depth and width. It is best to have at least two grow beds in your system rather than just one. This will allow you to clean out any plant roots between planting while still having your other grow bed working to keep the water clean and safe for the fish.

There are two different configurations of media-filled grow beds, flood and drain (also called ebb and flow) and continuously flooded. Flood and drain are the best, regardless of the types of plants you are planting, because it provides the best distribution of incoming nutrient rich water throughout the bed as well as adding aeration to the wetted media and plant roots where the bacteria live. This also adds dissolved oxygen to the water being flooded back into the bed and then returned to the fish tanks.

You will need a way to flow the water into the grow bed. The water entry point into the grow bed depends, in part, on the shape of your grow bed and how you plan on using it. With a flood and drain grow bed, the point of entry of your water is not critical; but it should have an unrestricted opening so as not to clog with fish waste solids. Do not attempt to spray your water into the grow bed, for the spray holes will clog up in short order (experience speaking here).

The best way to drain your grow bed is with a Bell Syphon. This is a device with no moving parts that, when the grow bed is filled with water, starts to syphon out all of the water in the grow bed down to a preset level before "breaking syphon". At that point, the syphon action stops; and the grow bed starts to refill. The design of this syphon is critical in order to get it to do its job in a timely manner. I'm not going into the design and construction of Bell Syphons here. This information can be found elsewhere on the web, as there are several different designs available. The syphons must be sized properly in order to remove the water from the grow bed in a fraction of the fill time and still function properly. Grow beds using a Bell Syphon have water continuously being flooded into them at a slower rate than the syphon drains the water out, so you get a flood and drain cycling action.

The more often you flood and drain your grow beds, the more dissolved oxygen will be added to the water returning to your fish tank. You should count on cycling your grow beds at least four times per hour. Not only does the design of the syphon influence the cycle timing, the rate at which you flow water into your grow bed, does as well. This cycle timing is one of the most critical parts of the design of an Aquaponics system. Needless to say, you will need enough pumping power to exchange most of the water in your grow beds four times an hour.

Keep in mind that once the grow bed media is in the grow bed, it will displace at least 50% (expanded clay) of the volume of the grow bed (more for gravel) leaving half or less of the original grow bed volume for water. This should be taken into account when sizing your water pump. The good news is, you may be able use a smaller pump requiring less electrical power as long as other pump sizing requirements are met (more on this in a later post).

Within the Aquaponics community, you will find differing opinions on the numbers I'm about to give you; but I believe them to be the most accurate based upon what I have learned from those with years of experience in building and testing different combinations of system sizes and ratios, as well as from my own experience in verifying these numbers. You can build an Aquaponics system any size you desire, for it is the ratios of the various component sizes that really mater. So, lets start with the ratio of the fish tank size in gallons to the grow bed container size in gallons. There should be about a one to one ratio between the fish tank and grow bed container size. This is assuming that you are using media filled grow beds.

Media filled grow beds are ones that use a growing media such as expanded clay or gravel to fill the beds. It has been found that the amount of grow bed volume needed to support a system is more related to the pounds of fish in the tanks and how much they are fed than the amount of water in the system. If you are using expanded clay as a grow bed media, a good rule of thumb for the size of grow beds is 6 gallons of grow bed (minimum) container size for every pound of fish you plan to have in your system at maximum fish grow-out size. If you plan on a ratio of six gallons of water per pound of fish in the fish tank, then this works out to about one gallon of fish tank capacity to one gallon of grow bed container capacity when using expanded clay as a grow bed media.

For gravel media in your grow beds, you should consider increasing the size (depth) of your grow beds by about 50% or decreasing the planned fish poundage by about one third. Some combination of these two adjustments might make more sense.

Many Aquaponics farmers are pushing these numbers in their systems and will argue for what they are doing. I am trying to give you what I believe are optimum parameters here for a system that will have the highest probability of working and allow you the greatest possibility of success as a first time Aquaponics farmer. Some live close to the edge and seem to get away with it, others are not so lucky.

In Part Three I will continue talking about System Design.

keith_r
02-10-2011, 07:05 AM
i'm interested in these threads, but do you have data to support statements like flood and drain is better than cf?

i'd like to see data that would support your point of view,,not trying to cause trouble or anything, but i've seen "advise" posted with nothing to back it up.. and i've seen other systems that are in conflict with your statments..

regarding gb depth, how did you arrive at that number?

are you selling ap products/services? (sorry, but i've been "invited" to several presentations about ap, and while they may have some good info, they have no data to backup statements!)

Oliver
02-10-2011, 12:10 PM
"i'm interested in these threads, but do you have data to support statements like flood and drain is better than cf?"

Good question. As far as data, most of the evidence is anecdotal and simple logic. It is well known that some plants won't grow well or at all in constant flow grow beds, for their roots need more oxygen than do other plants. Flood and drain supplies this needed oxygen while constant flow does not. Logically then, the bacteria living in the grow beds would do much better with more oxygen. Part of what I had edited out due to trying to keep it short was that we used to only flood and drain half of our grow beds. That was when our DO was low. Now we flood and drain all of them; and, along with the other changes, we have much better DO. It is just simple physics and common logic that the water flowing through a constant flow grow bed is not going to get as good of an even distribution of nutrients and oxygen as a flood and drain grow bed, which does a nearly complete grow bed purge.

"i'd like to see data that would support your point of view,,not trying to cause trouble or anything, but i've seen "advise" posted with nothing to back it up.. and i've seen other systems that are in conflict with your statements.."

I would be interested in the specific conflicting information and the data to support it as well.

"regarding gb depth, how did you arrive at that number?"

It is a number that has been tested by those who have been working with flood and drain aquaponics grow beds for many years. It has to do with the published surface area of the particular media with which you are working. I didn't go into the numbers here, again, for brevity. Also, as I stated earlier, I have built systems using these numbers and they work well.

One big argument is the removal of fish waste solids. Those who use deep (12" or more) grow beds generally find that they do not have a problem with over accumulation of these solids. Those with shallower grow beds tend to complain about the accumulation of fish waste solids. I hedge my bets on this by weekly adding heterotrophic bacteria, as I will talk about in a future post. After almost two years and twice in that time having to clean out the grow beds full of plants roots, I have found the solid fish waste problem not to exist. This, I believe, is due to the depth of the grow beds allowing time for the solids to break down. By digging into the grow beds while they are flooded, you do find solids in the water in the process of breaking down, but not accumulating in the bottom.

"are you selling ap products/services? (sorry, but i've been "invited" to several presentations about ap, and while they may have some good info, they have no data to backup statements!)"

Not here.

There is a lot of research available that shows the importance of DO levels needed for both plant and fish growth, and the science of nitrification clearly indicates its necessity. The flood and drain process also has been shown to increase oxygenation of the water in the grow bed, which gets returned to the fish tank. The deeper the grow beds, the more surface area there is for both the nitrification process to take place as well as oxygenation of the wetted surface area of the substrate media in the grow bed. The oxygen only goes a few molecules deep into the water surface, so the more surface area, the more oxygen is dissolved and eventually returned to the fish tank.

I need to impress the importance of high levels of DO in the system, for it is the prime ingredient that is required in every aspect of the process. Anything that one can do in the system design and operation to increase the DO will benefit the whole system. Unfortunately, this is usually mostly ignored, I believe, because of the price of DO meters.

Oliver

keith_r
02-10-2011, 01:37 PM
i appreciate your reply Oliver..
i'm a member of several forums (aquaponics, ponds etc) and try to learn as i go.. i was at a presentation for a guy selling systems, everything was galvanized, fish tanks, gb's.. and when i questioned him about it he stated that he'd been doing it that way for years with no issues.. on another forum i follow someone experienced some fish deaths, and had galv tanks (not lined), after this happened to a couple people someone got the smart idea to have their water tested and found toxic levels of metals that had leached from the tanks..

on the byap forum they are trialing 3 growbeds side by side from one ft, one is cf, one is flood and drain and one is timed flood and drain, the cf bed has been showing better performance of all but a couple of plants, it's easier to follow a recommendation when there is visual proof..

your point about DO levels has been demonstrated on many forums.. gb depth though, i've seen great performance out of "shallow" beds and planting things that don't need the depth, but personally i think deeper would be better, there's a system of one of the members here (TCLynx) that is using rubbermaid totes for gb's 20" deep, these aren't being "completely" drained because she drains out the side, again she shows tremendous results..

i take pretty much everything i read with a grain of salt, but with a well documented system (pictures/dates etc), including failures/issues etc beats the hell out of a verbal argument every time

i'd be interested to know how you arrive at that stocking density as well...

urbanfarmer
02-10-2011, 02:21 PM
i appreciate your reply Oliver..
i'm a member of several forums (aquaponics, ponds etc) and try to learn as i go.. i was at a presentation for a guy selling systems, everything was galvanized, fish tanks, gb's.. and when i questioned him about it he stated that he'd been doing it that way for years with no issues.. on another forum i follow someone experienced some fish deaths, and had galv tanks (not lined), after this happened to a couple people someone got the smart idea to have their water tested and found toxic levels of metals that had leached from the tanks..

on the byap forum they are trialing 3 growbeds side by side from one ft, one is cf, one is flood and drain and one is timed flood and drain, the cf bed has been showing better performance of all but a couple of plants, it's easier to follow a recommendation when there is visual proof..

your point about DO levels has been demonstrated on many forums.. gb depth though, i've seen great performance out of "shallow" beds and planting things that don't need the depth, but personally i think deeper would be better, there's a system of one of the members here (TCLynx) that is using rubbermaid totes for gb's 20" deep, these aren't being "completely" drained because she drains out the side, again she shows tremendous results..

i take pretty much everything i read with a grain of salt, but with a well documented system (pictures/dates etc), including failures/issues etc beats the hell out of a verbal argument every time

i'd be interested to know how you arrive at that stocking density as well...

I don't think there's a "one size fits all" type AP system. There are SO many variables you can't just say what works best for someone in California is going to work for someone in Florida. The type of plant, climate, and many other conditions can affect exact performance. I'm not saying anyone is right or wrong, but rather what you find what works best for you, well... works best for you! :mrgreen:

On the depths of the grow beds, I just learned today that the commonly held belief that a tree's root system mirrors the branches above is NOT true for Florida planted trees. They tend to spread out far and not deep, often times 3 times the length of the branches. This is because the roots simply don't have deeper soil to grow into... similar to shallow grow beds. Sure, we can discuss the microbes and so on and so forth, but I just want to point out that with evolved multicellular life forms, they tend to have advanced mechanisms for survival. If anything, it is a bit arrogant to believe we know best given our tiny amount of knowledge for all circumstances when there are more variables than there are facts or answers. Trail and error is the way to go while using what we do know as a GUIDE and NOT GOSPEL. Plus if it doesn't work out, you can rack up kills to become a REAL fish farmer, right? :lol:

Oliver
02-10-2011, 03:03 PM
keith_r

In writing this I knew that these kinds of questions and challenges were going to come up. That is why I took care in my wording and am saying that this is not cast in stone. I have to look at my post for in my mind I am several posts ahead of what is published. I find it gets a little confusing for me to keep track of what you have read.

The stocking densities are like everything else, a combination of others and my own experience. As our fish grew out, I watched carefully the system chemistry. As we planted different plants and watched them grow and some flower, I noticed the chemistry change. Later, as the fish got bigger and we fed them more food and a second planting happened, I noticed the chemistry changing as it did with the first planting. I also noticed that it was becoming more difficult to keep the system in the acceptable range and balanced. That was when I focused on increasing the DO in the water. Over time and a number of changes to the system it has come back into balance and stayed there. I keep a log of every change in the system and record all the numbers in it. This includes the usual water chemistry as well as the amount of food given the fish (automatic fish feeders with precise metering of food), tank temperatures, DO in each tank. pH, and TDS, as well as any fish death or tank change.

Once the fish reached one pound per three gallons of fish tank water, I again noticed a sensitivity in the balance. More DO was added and it again settled back down. At this point there is not much, short of adding pure oxygen to the water, that I can do to keep the system stable if I increase the poundage of fish; for the DO is currently between 6 and 7 ppm. So, I have concluded, as have others, that the one pound per three gallons of water, given the volume of grow beds I currently have in the system, is a maximum. This is where I came up with the number of 3.3 pounds of fish per gallon of grow bed capacity. The reason for the 3.3 pounds is because we only have five grow beds (due to space limitations) when ideally we should have six, so I have calculated the ratio to show our actual grow bed to fish density ratio. If I increase the number of grow beds (which will require a redesign of the system) then it should be possible to up the number of fish. But this will compromise the idea behind this series of posts, which is to tell how to build a simple Aquaponics system that will produce food without pushing the limits of Aquaponics design. I want people who are new to Aquaponics and are building and operating their first system to be successful.

By the way, we have some fry and fingerlings in one of our three connected (water exchange only, no fish exchange) tanks. As they grow out I will be keeping an eye on the chemistry as always and it will again challenge they system. It may be time then to harvest some fish, as we have yet to do that.

Oliver

Oliver
02-10-2011, 03:26 PM
urbanfarmer

"I don't think there's a "one size fits all" type AP system. There are SO many variables you can't just say what works best for someone in California is going to work for someone in Florida."

As long as the environment is the same (and it usually isn't) then the science will work the same. I agree that not everything can be distilled down to pounds, gallons and ratios. But, we do the best we can to understand what the process is and what is going on in any Aquaponics system and then apply what we learned in the next system, regardless of location. Even two identical systems in the same location will respond differently; which is only to say that regardless of what we may think, they really aren't identical after all.

"If anything, it is a bit arrogant to believe we know best given our tiny amount of knowledge for all circumstances when there are more variables than there are facts or answers. Trail and error is the way to go while using what we do know as a GUIDE and NOT GOSPEL. Plus if it doesn't work out, you can rack up kills to become a REAL fish farmer, right?"

The Aquaponics experience tends to weed out arrogance once some of your fish die. And, yes, this is just a guide; but my hope is that I have landed somewhere near the center of the bell curve when it comes to the advise I am giving here. Obviously, I am taking some risk in putting this information out on a forum; for I know that not all will agree with these suggestions. But, that is why I asked JCO to unlock this area so we could have a good and lively debate.

Oliver

urbanfarmer
02-10-2011, 04:34 PM
I think you're doing a great job Oliver! Very few people put in the time and dedication to help others. Keep up the hard work. :mrgreen:

stucco
02-10-2011, 05:06 PM
I think you're doing a great job Oliver! Very few people put in the time and dedication to help others. Keep up the hard work. :mrgreen:


+1

rfeiller
02-10-2011, 08:03 PM
+ another.

used as a starting point guide for those of us without the experience will at least minimize the failures and maximize the possibilty of success. we can adapt any variations from there as deemed needed.

a little success goes a long way to help keep new folks in the aquaponics program and insure further successes.

i appreciate the unselfish manor in which the members are willing to help each other to have success.

rich

dufflight
02-10-2011, 09:14 PM
I've got paw paw trees in cf gb's with 20mm of water running over the media :shock: and they are growing better than others in f&d. And paw paws are not ment to like wet feet. As pointed out above. Lots of different way to do AP.

keith_r
02-11-2011, 06:20 AM
i'm enjoying the articles as well, and i appreciate the effort.

TCLynx
02-11-2011, 11:50 PM
Once the fish reached the three pounds per gallon of fish tank water, I again noticed a sensitivity in the balance. More DO was added and it again settled back down. At this point there is not much, short of adding pure oxygen to the water, that I can do to keep the system stable if I increase the poundage of fish; for the DO is currently between 6 and 7 ppm. So, I have concluded, as have others, that the three pound per gallon of water, given the volume of grow beds I currently have in the system, is a maximum. This is where I came up with the number of 3.3 pounds of fish per gallon of grow bed capacity. The reason for the 3.3 pounds is because we only have five grow beds (due to space limitations) when ideally we should have six, so I have calculated the ratio to show our actual grow bed to fish density ratio. If I increase the number of grow beds (which will require a redesign of the system) then it should be possible to up the number of fish. But this will compromise the idea behind this series of posts, which is to tell how to build a simple Aquaponics system that will produce food without pushing the limits of Aquaponics design. I want people who are new to Aquaponics and are building and operating their first system to be successful.

Oliver

Oliver, did you really mean to say 3 pounds of fish per gallon? Or is that an inversion and did you really mean one pound of fish per 3 gallons? Earlier on you said 1 pound per 3 gallons of fish tank which I suppose might be ok with very forgiving fish like tilapia but when some one quoted this little section to me :shock: well my eyes kinda bugged out. Please tell me that the numbers just got a bit inverted here and you really meant 1 pound of fish per 3 gallons of water.

Oliver
02-11-2011, 11:55 PM
Oliver, did you really mean to say 3 pounds of fish per gallon? Or is that an inversion and did you really mean one pound of fish per 3 gallons? Earlier on you said 1 pound per 3 gallons of fish tank which I suppose might be ok with very forgiving fish like tilapia but when some one quoted this little section to me :shock: well my eyes kinda bugged out. Please tell me that the numbers just got a bit inverted here and you really meant 1 pound of fish per 3 gallons of water.

Oops. Thanks for catching that. I will edit it right away. It was my lexdisia messing with me, once again.

Oliver

Oliver
02-12-2011, 01:43 AM
Thanks to all who gave me a +, for I do appreciate it.

badflash
02-12-2011, 07:55 AM
My number is 5 gallons per pound of fish, and even that is pushing it. You need to have some margin for power outages, pump failures, etc. I keep small air pumps on a computer UPS. These go a long time as they only draw about 10 watts each and can hold you until the power comes back or you get home and get your generator going.

TCLynx
02-12-2011, 08:39 AM
I personally also go for the lower density stocking. I'm recommending more like 1 fish per ten gallons of fish tank with 20 gallons of grow bed media filtering for it. Then again, I grow fish big and either use a sump on a CHIFT PIST system or an Aquaponics indexing (sequencing) valve but that is all more complexity than most beginners want.

rfeiller
02-12-2011, 09:19 AM
fish density is a tricky deal, a few small goldfish will produce tremendous amounts of nitrates. i've cut back from 20 small goldies to 10 per 100gal res with a 4x4 tray loaded with plants. i do feed the fish to insure their proper growth. with that ratio i could cut the power to them for days. my point being

TCLynx
02-12-2011, 09:27 AM
Right, 1 lb per 3 gallons is MAX.
With media bed aquaponics you DO NOT NEED to stock that much. If fish are not your primary goal, it doesn't take much fish to support the veggies if you are leaving the solids in the system.

I know of systems where a whole greenhouse (well not a big one) is supported by only a hand full of goldfish and has great veggie growth.

urbanfarmer
02-13-2011, 10:01 AM
Oliver, looking good. I have one question. You mentioned 3.3 gallons of grow bed per pound of fish. I have no problem with guestimates and the like especially when someone has as much as experience as you, but 3.3? That's rather accurate for a guess. Can I ask how you arrived at this calculation? I realize your guide is supposed to be very practical information (hence the omission); so, I really only want to know to satisfy my selfish curiosity! :lol:


I know of systems where a whole greenhouse (well not a big one) is supported by only a hand full of goldfish and has great veggie growth.
I know a lot of people might not agree with that, but you are absolutely right. In fact, newer research into aquaponics has shown that this is exactly the case... assuming there is near constant flow.

TCLynx
02-13-2011, 10:49 AM
I know of systems where a whole greenhouse (well not a big one) is supported by only a hand full of goldfish and has great veggie growth.
I know a lot of people might not agree with that, but you are absolutely right. In fact, newer research into aquaponics has shown that this is exactly the case... assuming there is near constant flow.

Actually, I wouldn't even assume near constant flow, timed flood and drain work for this too. But when you start getting into things like this you have to start basing things on how the plants are doing and how the fish and bio-filter are doing so it isn't really a cut and dried 101 type thing anymore.

urbanfarmer
02-13-2011, 12:12 PM
I know of systems where a whole greenhouse (well not a big one) is supported by only a hand full of goldfish and has great veggie growth.
I know a lot of people might not agree with that, but you are absolutely right. In fact, newer research into aquaponics has shown that this is exactly the case... assuming there is near constant flow.

Actually, I wouldn't even assume near constant flow, timed flood and drain work for this too. But when you start getting into things like this you have to start basing things on how the plants are doing and how the fish and bio-filter are doing so it isn't really a cut and dried 101 type thing anymore.
Hm, depends on the timing I guess, but it has to be near constant flow. The research supports this, and as a Master Gardener I can also state this because it is our official stance (and this is also based off University of Florida research in our publications).

P.S. I am excited about our tour, and I can't wait to see your setup! YAY! :D

P.P.S. I want some catfish, but I'm not sure how much (not a lot though, maybe a few dozen)... I will let you know elsewhere; just don't forget me please!!!!!

badflash
02-13-2011, 02:26 PM
Please post a link to these publications.

TCLynx
02-13-2011, 03:39 PM
Yes, please I hadn't realized that UF had gotten into Aquaponics (must admit I haven't searched it in a couple years.)

TCLynx
02-13-2011, 03:58 PM
I know of systems where a whole greenhouse (well not a big one) is supported by only a hand full of goldfish and has great veggie growth.
I know a lot of people might not agree with that, but you are absolutely right. In fact, newer research into aquaponics has shown that this is exactly the case... assuming there is near constant flow.

Actually, I wouldn't even assume near constant flow, timed flood and drain work for this too. But when you start getting into things like this you have to start basing things on how the plants are doing and how the fish and bio-filter are doing so it isn't really a cut and dried 101 type thing anymore.
Hm, depends on the timing I guess, but it has to be near constant flow. The research supports this, and as a Master Gardener I can also state this because it is our official stance (and this is also based off University of Florida research in our publications).

P.S. I am excited about our tour, and I can't wait to see your setup! YAY! :D

P.P.S. I want some catfish, but I'm not sure how much (not a lot though, maybe a few dozen)... I will let you know elsewhere; just don't forget me please!!!!!


Please post a link to these publications.


Yes, please I hadn't realized that UF had gotten into Aquaponics (must admit I haven't searched it in a couple years.)

OOH, I think this is gonna need to be split out into another thread as it doesn't really pertain to Aquaponics 101.

I just did a little search and the first thing I'm reading.......... definitely need the mod's to move this into a separate discussion as there is lots to discuss! First page I read and I can see a huge can of worms opening up.

urbanfarmer
02-13-2011, 08:12 PM
Please post a link to these publications.
http://edis.ifas.ufl.edu/hs408

120 pages of fun. A little repetitive, but otherwise eye opening.

urbanfarmer
02-13-2011, 08:16 PM
OOH, I think this is gonna need to be split out into another thread as it doesn't really pertain to Aquaponics 101.

I just did a little search and the first thing I'm reading.......... definitely need the mod's to move this into a separate discussion as there is lots to discuss! First page I read and I can see a huge can of worms opening up.

WHAT DID YOU FIND??? Post it here: TCLynx what did you find? (http://www.diyaquaponics.com/forum/showthread.php?762-TCLynx-what-did-you-find)

badflash
02-13-2011, 08:17 PM
Please post a link to these publications.
http://edis.ifas.ufl.edu/hs408

120 pages of fun. A little repetitive, but otherwise eye opening.

Mybe another document? That one was 8 pages on Foliar-Applied Micronutrients.

urbanfarmer
02-13-2011, 11:12 PM
Oh how strange... I wonder how I got the 120 page paper... okay, let me check tomorrow what the heck is going on.

urbanfarmer
02-13-2011, 11:23 PM
http://etd.fcla.edu/UF/UFE0019861/tyson_r.pdf

utahgal
05-21-2011, 08:25 AM
Hello all

I realize this may be a little dated in this thread, but as a total newbie, I really appreciate Aquaponics 101. I also understand that one size doesn't fit all and that this thread is not gospel. I understand that what works for me in Utah, probably will not work for someone in Australia and vise versa. Case in Point. Tilapia are considered an invasive species in Utah and therefore cannot be used in my system. Prawn of all types (craws etc) are also considered invasive. So my best option at the moment is goldies. After I figure out what I am doing, then I will have to decide on another type of fish. Probably trout, (slow growing) as well as catfish, koi, bass, etc.

My system is the barrel system. No innovations applied, and done exactly to specs in Mr. Hughey's manual lol. I figured to go with a tried and true system to learn from before I started making changes. We are in the process of being certified organic so are on first name basis with more than one state official that we can bounce questions off of.

At the moment my system is running with no fish or plants yet. Nearest goldfish is almost 2 hours away 8(. We are on well water and system built in a green house. There are so many things I don't know, I don't even know what they are. Being able to get ideas and references from here I can check out other options and see if something else would better fit my situation.

Again, I really appreciate and thank all contributors for this forum and maybe in the future I will be able to post and answer or offer options instead of asking all the questions.

Cindy

urbanfarmer
05-21-2011, 09:36 AM
Don't hesitate to ask. :mrgreen: Feel free to start a new thread, post pictures, etc!

rfeiller
05-21-2011, 09:54 AM
Welcome utahgal welcome.
Everything we know is evolving and improving so jump on board! :)

chesapeakebaybe
07-14-2011, 08:05 AM
Oliver, I'm sorry that some people are giving you such a hard time. It's like the saying goes "you can't please all the people all the time." Yet, I am another person who is truly grateful for your generous sharing of what is working for you... it is giving me a good starting point as I plan my own aquaponics system.

jlawsonz
07-22-2011, 07:47 AM
Keep in mind that once the grow bed media is in the grow bed, it will displace at least 50% (Hydroton) of the volume of the grow bed (more for gravel) leaving half or less of the original grow bed volume for water. This should be taken into account when sizing your water pump.

If you are using Hydroton as a grow bed media, a good rule of thumb for the size of grow beds is 3.3 gallons of grow bed (minimum) container size for every pound of fish you plan to have in your system at maximum fish grow-out size. If you plan on a ratio of three gallons of water per pound of fish in the fish tank, then this works out to about one gallon of fish tank capacity to one gallon of grow bed container capacity when using Hydroton as a grow bed media.


Oliver, I've been searching for the answer to this and have not yet found it related to grow bed volumes.

Based on the numbers you used above.
3.3gallons of grow bed
1 pound fish
3 gallon fish tank

Does the grow bed hold 3.3gallons of water with the Hydroton or is this 3.3gal capacity empty?

I'm planning out my system and want to ensure I have appropriate sized tank. I'm digging for an in ground tank with internal dimensions of 6'x15' at 3' depth. That comes out to 2,000 gallons for the tank which I calculate that I need 267 square feet of garden space at 12" depth and can handle about 660# fish.
Does that seem right?

I'm using the formula of 1cu.ft.=7.48gal.

Oliver
07-22-2011, 11:22 AM
Does the grow bed hold 3.3gallons of water with the Hydroton or is this 3.3gal capacity empty?
That would be container size (empty).

Oliver

TCLynx
07-22-2011, 04:36 PM
I would personally recommend a lesser fish load when planning a system. Like something closer to twice that amount of gravel bed per pound of fish. Once experienced you may be able to get away with more fish but if you are having to ask how much fish you can stock, you are really not prepared to handle a system stocked that heavily. One fish per cubic foot of gravel (aprox 7.5 gallons of gravel bed) is a very reasonable amount to start with.

Scupper
09-05-2011, 09:30 PM
Oliver, thanks for the forum. It is very helpfull.

My question relates to fish tank and growth bed size ratios in terms of fish stress. Im not trying for pin point accuracy in terms of volume just a general understanding.

If I understand the 1 to 1 ratio as presented, a flood and drain system with 2 growth beds will eventually cycle to a point where both growth beds are filled with water (Just before draining). Taking into account the volume of the media, this would require of the water from the fish tank. Hypothetically speaking a 24 high fish tank would then be temporarily lowered to approximately 12. Assuming this is true;

1. Would the lowered fish tank level cause any stress to the fish?

2.Would this argue for a sump tank to keep the fish tank level constant?

Thanks

urbanfarmer
09-06-2011, 04:48 AM
Oliver, thanks for the forum. It is very helpfull.

My question relates to fish tank and growth bed size ratios in terms of fish stress. Im not trying for pin point accuracy in terms of volume just a general understanding.

If I understand the 1 to 1 ratio as presented, a flood and drain system with 2 growth beds will eventually cycle to a point where both growth beds are filled with water (Just before draining). Taking into account the volume of the media, this would require of the water from the fish tank. Hypothetically speaking a 24 high fish tank would then be temporarily lowered to approximately 12. Assuming this is true;

1. Would the lowered fish tank level cause any stress to the fish?

2.Would this argue for a sump tank to keep the fish tank level constant?

Thanks
1) Most definitely, no.

2) That's up to you, but it's unnecessary with gravel grow beds.

davidstcldfl
09-06-2011, 05:36 AM
Like UF said...it's up to you.
I use a sump, which keeps my fish tanks water at a constant height. Which makes the fish happier..they told me so... :D :lol:
The advantage to a sump is, with the added volume of water, the tempt, DO level, ph, ect remains more stable. The smaller the system, the faster the 'swings'.

TCLynx
09-06-2011, 06:13 AM
It will also depend on the type/number of fish as to how stressful they will find 40% water level fluctuations. If you are stocking as if you have a 2:1 ratio then the number of fish will probably mean that the water level fluctuation would be too much and you would need to mitigate the fluctuation with extra water from a sump or some means of sequencing the flow to the grow beds. However, if you are stocking the fish tank very moderately compared to the volume of your grow beds with a 1:1 ratio of grow beds to fish tank then the fish will probably be ok with the fluctuation.

Extra water in a sump tank to handle the fluctuations is good as long as you are not tempted to stock fish in that tank too. There are also some handy things you can use a sump tank for. If you let your fish tank water flow through grow beds before going to the sump tank, you get a "clean water sump" with water appropriate to go to things like towers, NFT pipes, or even raft beds as well as being pumped back to the fish tank.

urbanfarmer
09-06-2011, 08:56 AM
Like UF said...it's up to you.
I use a sump, which keeps my fish tanks water at a constant height. Which makes the fish happier..they told me so... :D :lol:
The advantage to a sump is, with the added volume of water, the tempt, DO level, ph, ect remains more stable. The smaller the system, the faster the 'swings'.
Oh, very true. The more volume of water you have the more "stable" the system is.

I think they lied to you about the fish being happier. I have a written statement from my fish that says they prefer the up and down. They get bored, or so they claim! :lol:

connection2wealth
09-29-2011, 12:45 AM
Hi,

Just member of this forum a minute ago as I did searching of any valuable topics regarding Aquaponics and found this very interesting forum. I am a month old Aquaponics hobbyist and constructed my own design applying the methods(NFT,Media-based,and Raft) I learned from the net.

Now, I have a question if my design will work. Here's the picture.

http://i53.tinypic.com/30ldrif.jpg

davidstcldfl
09-29-2011, 04:58 AM
Hi connection2wealth, welcome to the forum... :)
It looks like you have been busy reading and building. It's too late to warn you, that this is addictive... :lol:

Please 'copy and paste' this into 'your own' thread in the section...."BACKYARD SYSTEMS".
I'm sure everyone will want to greet you, comment and ask questions about your system 'over there.'
Also, in 'your info'...if you would list what state and general area you are located....you might just find out you have some other 'aquapons' near you. It's nice to get to actually meet and check out other peoples systems.. :D
Thanks connection2wealth.

urbanfarmer
09-29-2011, 08:14 AM
Hi,

Just member of this forum a minute ago as I did searching of any valuable topics regarding Aquaponics and found this very interesting forum. I am a month old Aquaponics hobbyist and constructed my own design applying the methods(NFT,Media-based,and Raft) I learned from the net.

Now, I have a question if my design will work. Here's the picture.

http://i53.tinypic.com/30ldrif.jpg
It would have been better to put the gravel beds before the NFT pipes because it would act as a filter. I see you have some filters before it, which will help. If too many solids build up on the roots in the NFT it will suffocate the plant. Gravel grow beds are good at collecting solids, and we like them there! :D

davidstcldfl
09-29-2011, 08:40 AM
Let's show some respect for Oliver.....and keep 'his' thread 'on topic'. I'm just as guilty of doing the same thing, if not more so... :oops:

"IF" JCO has to put on his cape and big boots.....
he's not looking to take names... :P

Shas
12-05-2011, 01:51 PM
This is excellent information, Oliver,
and delivered in a very accessible and practical way.
Kudos and thanks!
Don't change a thing!