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Jeff
03-07-2012, 12:58 PM
Ok, I need some reassurance and opinions. I am about to purchase my tanks and GB's tomorrow and drop enough money to make my wife give me "that look." You know the one I'm talking about!

Anyway, I am starting to question my original design.

My original design was pretty standard: tank pumps to 3 grow beds......grow beds drain to tank. Repeat.

I like this for the simplicity, and the extra aeration the tank will get from the draining grow beds, but I do see three main things that I may want to avoid. First off, with the pump in the fish tank, it's going to be the one sucking up the solids, and that could wear on the overall lifespan of the pump itself. Secondly, the water level in the tank will constantly be lowering and raising. Thirdly, while minor, there is also the chance of sucking up little fish.

Now I am thinking of a CHIFT PIST design. That is, I would have the fish tank gradually drain via a venturi drain, and feed the three grow beds. The grow beds would drain below into a sump tank......and the sump tank would pump back to the fish tank. The advantage to this is that the pump is basically handling filtered water. Most fish solids would be caught by the grow media, thus reducing any strain on the pump.

Sort of like this, only with THREE grow beds and a bell siphon in each:

http://backyardaquaponics.com/forum/download/file.php?id=18707

My only concern with the second method is the following:

1. With the fish tank draining into the three grow beds (without being PUMPED into them), is the force/pressure coming from the tank enough to feed into the furthest grow bed? I hope that makes sense. I planned to put ball valves on each grow bed so I assume that I can adjust it so that the furthest bed gets water in there.

2. I was concerned that since the grow beds would drain to the SUMP, that this would mean less oxygen for the fish tank. However, am I correct in assuming that if the SUMP is aerated from the splashing, draining grow beds, that this oxygenated water is still given to the fish tank via the pump, so essentially, there's no real difference or trade off here? NOTE: I still plan to have an air stone in the fish tank.....but the more oxygen I provide, the better for the system.

3. Would you say this second CHIFT PIST design is the way to go over the more simplistic one I originally planned? I would plan to have the fish tank and grow beds all leveled out on some concrete blocks, with the sump tank BELOW the grow beds.

Thanks in advance for your replies!

Oliver
03-07-2012, 02:55 PM
I like this for the simplicity, and the extra aeration the tank will get from the draining grow beds, but I do see three main things that I may want to avoid. First off, with the pump in the fish tank, it's going to be the one sucking up the solids, and that could wear on the overall lifespan of the pump itself. Secondly, the water level in the tank will constantly be lowering and raising. Thirdly, while minor, there is also the chance of sucking up little fish.

Now I am thinking of a CHIFT PIST design. That is, I would have the fish tank gradually drain via a venturi drain, and feed the three grow beds. The grow beds would drain below into a sump tank......and the sump tank would pump back to the fish tank. The advantage to this is that the pump is basically handling filtered water. Most fish solids would be caught by the grow media, thus reducing any strain on the pump.

My only concern with the second method is the following:

1. With the fish tank draining into the three grow beds (without being PUMPED into them), is the force/pressure coming from the tank enough to feed into the furthest grow bed? I hope that makes sense. I planned to put ball valves on each grow bed so I assume that I can adjust it so that the furthest bed gets water in there.

2. I was concerned that since the grow beds would drain to the SUMP, that this would mean less oxygen for the fish tank. However, am I correct in assuming that if the SUMP is aerated from the splashing, draining grow beds, that this oxygenated water is still given to the fish tank via the pump, so essentially, there's no real difference or trade off here? NOTE: I still plan to have an air stone in the fish tank.....but the more oxygen I provide, the better for the system.

3. Would you say this second CHIFT PIST design is the way to go over the more simplistic one I originally planned? I would plan to have the fish tank and grow beds all leveled out on some concrete blocks, with the sump tank BELOW the grow beds.

Thanks in advance for your replies!

Jeff,

The main issue I have with this type of design is just the opposite of your concerns. It is important that all fish waste solids are run through the pump. I don't believe it will decrease its life enough to notice, if at all. The reason you want the solid fish waste to go through the pump is so they will be macerated. Not to do so will place fully sheathed worm like solids into the grow beds (if they get there) causing a possible accumulation of solid fish waste in the grow beds, as some have reported. By macerating the solids, they then become suspended solids with lots more surface area allowing for much faster mineralization by the heterotrophic bacteria in the system, thereby preventing them from accumulating.

Also, by regulating the flow to the grow beds, as you suggest and I recommend in order to set their cycle timing, the upward flow from the fish tank through the vertical pipe from the fish tank bottom will be very slow and much of the heavier than water solids won't make the trip but will accumulate in the pipe. Those solids that do make the trip up will be moving slowly through the plumbing and will also accumulate there. You will have no way of forcing them out without disconnecting your plumbing and blowing then out with higher pressure water from, perhaps, a garden hose.

As to the water level going up and down in the fish tank, unless you have designed your system with too much grow bed volume for the size of fish tank, then that won't be a problem while using a more "standard" configuration of a lower to the ground fish tank and elevated grow beds.

By placing the pump in the fish tank, it will macerate the solid fish waste as well as supply you with some extra pumping power (assuming proper pump selection) thereby allowing you to take some of the pump pressurized water at the last grow bed inlet at the end of the line and jet it back into the fish tank. This will allow for a higher velocity of water through the pressurized plumbing thereby carrying more macerated solids to the grow beds where they can be broken down into dissolved solids. This jetting action will add some dissolved oxygen (DO) to the fish tank. In addition, by fully opening the grow bed inlets (one at a time) it will cause the full force of the pump to blow through any accumulated fish waste solids in the plumbing into the individual grow beds. This should be done on a weekly basis at a minimum.

As for the baby fish getting into the pump, you can always add some fine screening (non metal) to the pump intake while they are small. I have only had one fish make it through the pump and it apparently grew in the plumbing, for when it came out into the grow bed it was much too large to have gone through the pump openings at its current size.

Oliver

Jeff
03-07-2012, 04:02 PM
I appreciate the response. You brought up some points I hadn't yet considered. I THINK with my original design, I should be good as far as water volume issues. Technically, I have slightly more grow bed space than fish tank:

Fish Tank: 110 gallons
Grow Beds: 3 x 40 gallons

So when I initially set the system up (no plants or fish), how do you go about FILLING it with water? Do you fill only the fish tank and let it pump water to all three grow beds until the water level in the fish tank reaches a certain height? I don't want to overfill or underfill it, but I don't know how much is too much when the system is constantly flooding and draining multiple beds into one tank.

And one other question. Given my design idea (with one tank flowing to three beds), are you suggesting that on the FURTHEST grow bed, that instead of capping the line, have it also return back to the tank? Keep in mind that I plan to put a T-connector on the pump right above the tank for a spray bar to 1) help aerate the water, and 2) release some of the water pressure. It's a 500gph mag drive pump.

davidstcldfl
03-07-2012, 06:55 PM
Jeff, with the 1st design you had.....your fish tank won't go up and down as much as you think it will.
1st- even if you fill it to the very top with media, the water will be an inch or two below that. ( you don't want the media surface getting wet...it'll grow algee.)
2nd- there is always some water left in the bottom of the GB after the siphon stops....maybe as much as 2 inches.
3rd- If you use river rock, they can displace up to 60% of the growbed volume.

You may have as little as 13-14 gals draining out of each GB....even if all 3 fill at one time...your fish tank may lose as little as 39 gallons.
Make sure to put a cover over the fish tank. That way you can fill it almost to the top and not worry about tilapia jumping out. Plus, it keeps leaves and junk out.

If you pump the solids like Oliver suggested....I'd skip the spray bar. It may plug up a lot.
I think your right Jeff....I think Oliver was saying to go past the 3rd grow bed with pipe, back to the fish tank. I'd also put a ball valve on that line, in addition to one on each bed.
Between the 3 grow beds draining and the pump spraying 'some' back to the FT...you should be doing pretty good on the DO side ... :D

Jeff
03-07-2012, 07:12 PM
Hi David - Thanks for the reply.

I think I am going to splurge on hydroton for the growing media, even though it's going to cost me like $400.00. Go big or go home, right! Of course, I may want to rethink that plan after I do all the plumbing on my system. I debated using red lava rock, but I have literally heard opposite opinions on it. Some LOVE it, others despise it. Do you have thoughts on it either way? I hear some river rock can be hell on the pH levels, even if it doesn't contain limestone.

I also want to make sure I understand what you're saying about the spray back in the fish tank. Which are you saying below:

1. Run a t-connector off the pump, BEFORE the grow beds, to feed water to the tank.....but leave off the spray bar. Simply let it pour out of the PVC because small spray holes will clog....OR

2. Don't run any initial spray back off the pump to the tank. Rather, wait until AFTER it passes the third grow bed, and then have the line drain back into the tank?

Also, I do plan to wrap some insulation around the fish tank AND fashion some kind of insulated cover for the top of it. Unfortunately, I am hearing that it's not legal to purchase tilapia in California (how can THAT be true?). So I am hoping I can find another aquaponics lover nearby who may point me to a source, or would have any for sale.

davidstcldfl
03-07-2012, 08:20 PM
I think I am going to splurge on hydroton for the growing media, even though it's going to cost me like $400.00.
It's very easy to stick a plant in to it. It doesn't seem to hold the plants in place as well as river rock. Some do a base of river rock, and top it with $/hydroton

I hear some river rock can be hell on the pH levels, even if it doesn't contain limestone.
Never heard that...?

I debated using red lava rock, but I have literally heard opposite opinions on it. Some LOVE it, others despise it.
It 's hard to dig in... :roll: I have heard (not sure if it's true...don't know how they could sell it if it's true..?) that some lava rock is sold after acting as filters for commercial apps and may contain chemicals.

Unfortunately, I am hearing that it's not legal to purchase tilapia in California (how can THAT be true?).
Think you can in S CA, but not in N CA...? Hmmm....it gets cold in the North CA, so they'll most likely die in nature, but it's OK to have them where it's warm...???
But Hey, there are a lot of things in CA that make me wonder...?... :P :lol:
see what Badflash wrote....page 1 of this link...
State Tilapia Regulations (http://www.diyaquaponics.com/forum/showthread.php?636-State-Tilapia-Regulations)

Jeff
03-07-2012, 09:00 PM
I hear some river rock can be hell on the pH levels, even if it doesn't contain limestone.
Never heard that...?


I probably should have clarified. I have read on other forums that they purchased river rock that didn't claim to have limestone, but they noticed the pH level's still spiked, which they attributed to hidden limestone or something.

Anyway, I will probably go to Home Depot to see what they have, and then post some feedback here if I have any questions. I am assuming that if I see something that looks small, and doesn't contain limestone, then I should techinically be good, right?




Unfortunately, I am hearing that it's not legal to purchase tilapia in California (how can THAT be true?).
Think you can in S CA, but not in N CA...? Hmmm....it gets cold in the North CA, so they'll most likely die in nature, but it's OK to have them where it's warm...???
But Hey, there are a lot of things in CA that make me wonder...?... :P :lol:
see what Badflash wrote....page 1 of this link...
State Tilapia Regulations (http://www.diyaquaponics.com/forum/showthread.php?636-State-Tilapia-Regulations)

I too have heard that they're legal in southern CA but not northern where I am at. Hopefully, one of the members on this forum who live near me will have some secret sources, or at least point me to some local fish suppliers that will work good in this environment.

I will have to check out that Badflash link you gave me. Thanks for the response! :)

bsfman
03-07-2012, 09:32 PM
I think I am going to splurge on hydroton for the growing media, even though it's going to cost me like $400.00. Go big or go home, right! Of course, I may want to rethink that plan after I do all the plumbing on my system. I debated using red lava rock, but I have literally heard opposite opinions on it. Some LOVE it, others despise it. Do you have thoughts on it either way? I hear some river rock can be hell on the pH levels, even if it doesn't contain limestone.

I've used hydroton, but now only use it in my strawberry towers for the lighter weight advantage. For a flood and drain bed, I'm a big fan of pea gravel. Hydroton does not support the plants nearly as well as pea gravel. It's messy too. I have little hydroton clay balls all over my backyard that got pulled up and rolled away when I harvested rooted plants. Pea gravel works much better for me. And it's WAY cheaper too!

But you could decide for yourself. Try one GB with hydroton and the others with pea gravel. If, after a cycle or two of crops, you think the hydroton works better, then you could upgrade to 100% hydroton.

Personally, I would avoid lava rock altogether. But if you want, try one GB with it as a test too. You can do one bed with pea gravel and one with lava rock for way less than the other one you do with hydroton.

Oliver
03-07-2012, 11:35 PM
This Tilapia in California question has come up before so I wrote a little document just for this purpose. So, here it is:

By the way, the folks at Fish and Game are giving out incorrect information. They are saying that all Tilapia are illegal north of the Tihachapi mountains. They haven't read their own code. Only Tilapia zilli*(Redbelly Tilapia) are listed with that in mind (see below).

As far as Blue, Banded and Nile Tilapia, they are banned in all of California. You can raise*Oreochromis*Mossambica and Oreochromis*Hornorum Tilapia anywhere in the state.

Here is the extracted applicable portion of the "code" which is different from a law and if you have enough money, time and will, you could fight it.

California State Laws Governing Private Possession of Exotic Animals
CAL. CODE REGS. Tit. 14 §671 -- Importation, Transportation and Possession of Live Restricted Animals
(a) It shall be unlawful to import, transport, or possess alive animals restricted in subsection (c) below except under permit issued by the Department of Fish and Game. Permits may be issued by the department as specified herein and for purposes designated in Section 671.1 subject to the conditions and restrictions designated by the department. Except for mammals listed in Fish and Game Code Section 3950 Fish & Game or live aquatic animals requiring a permit pursuant to Fish and Game Code Section 2271 Fish & Game, no permit is required by this section for any animal being imported, transported, or possessed pursuant to any other permit issued by the department. Cities and counties may also prohibit possession or require a permit for these and other species not requiring a state permit.
(b) The commission has determined the below listed animals are not normally domesticated in this state. Mammals listed to prevent the depletion of wild populations and to provide for animal welfare are termed "welfare animals", and are designated by the letter "W". Those species listed because they pose a threat to native wildlife, the agriculture interests of the state or to public health or safety are termed "detrimental animals" and are designated by the letter "D". The department shall include the list of welfare and detrimental wild animals as part of DFG MANUAL No. 671 (2/25/92) IMPORTATION, TRANSPORTATION AND POSSESSION OF RESTRICTED SPECIES, to be made available to all permittees and other interested individuals.
(c) Restricted species include:
(5) Class Osteichthyes - Bony Fishes
(O) Family Cichlidae - Cichlids
1. Tilapia sparrmani*(Banded Tilapia) (D).
2. Tilapia zilli*(Redbelly tilapia) (D), except permits may be issued to a person or agency for importation, transportation, or possession in the counties of San Bernardino, Los Angeles, Orange, Riverside, San Diego, and Imperial.
3. Tilapia aurea*(Blue tilapia) (D).
4. Tilapia nilotica*(Nile tilapia) (D).


As you can see, not all species of Tilapia are listed, so it is ok to raise them.

I hope this answers your questions.

Oliver
Aquaponics USA

bcotton
03-08-2012, 11:06 PM
For the record.

1)I have tried both methods and i prefer the fish tank overflowing into the grow beds and the pump in the sump like your drawing.
2) i have tried hydroton and expanded shale and all things considered i prefer the expanded shale over hydroton
a) it's 1/7th the cost
b) similar weight, pourous
c) hydroton wins the ph neutral bout, but i consider this a plus and a minus for expanded shale. buffering a little ph isnt all bad as long as it's within an acceptable range.
d) i have never found expanded shale larger than pea sized )even though it's often advertised at 3/8". I used to consider this a negative too, but a year later and i dont have any clogging issues that i can speak of and i argue that the hydroton is too big as my solid slip right through the bed and fall into the sump.
e) while i cant say i have ever complained about hydroton not supporting my plants.. the expanded shale does do a better job of holding on to the plants and i could see it being an annoyance in some situations.

3)i dont worry about macerate solids because i use red wiggler worms in my grow beds and they seem to do just fine with breaking down solids. If you have too many solids they have this feature where they reproduce until the food and livestock balances out.. mother nature is cool about that.

4) I have had pump breakage that i attribute to solid buildup, but through my own experimentation and reading others opinions, i now hypothesize that the on/off cycles of pumps tend to cause the higher mortality rates. If you are able to design your system to have the pump on at all times, that is probably best for the pump.


fwiw, i do use an air pump and air stones to make sure my DO stays high.. This probably wouldnt be necessary if i didnt live in texas and expect 60+ days around and above 100 degrees.

I have also been experimenting with air lift pumps which pump water and oxygenate it with the same power... They are relatively power efficient... and they have no moving parts (propellers) under water that can get damaged by solids, sand or rocks.

This is just some things to think about. I truly believe there is no absolute right way to do things and your personal situation will dictate what is right for you.


brian

Jeff
03-09-2012, 08:51 AM
Brian - Thanks for the awesome response. I am still undecided on growing media. I am trying to get whatever I can locally (Home Depot, Ace Hardware, Orchard Supply, Tractor Supply Co), and sometimes they just don't have what I'm looking for. I think the lava rock is no longer an option for me. It's between pea gravel, river rock, expanded shale, or Hydroton if I feel like giving myself a minor heart attack in the wallet department.

Let me ask you this. With your pH problems you've had.....is it a constant battle, or does it eventually get down to a steady level without you needing to add anything to it for buffering it?

I went out and purchased my grow beds and fish tank yesterday....WOOHOO! I think I am not going with a CHIFT PIST system, only because I don't have the room nor space to raise the tank above the grow beds for feeding them. Since the tank is going to be UNDER the beds, I have decided to initially create this system the old fashion way.

When the time comes to move the setup to a larger space, then I think I will go with a larger tank in that kind of setup.

foodchain
03-09-2012, 12:03 PM
Gonna agree with Brian on the pumps. On/Off kills them, solids kills them. Problem I have with air lift is head pressure. I can't seem to get more than about 4 inches or so.

foodchain
03-09-2012, 12:04 PM
Trust Brian on the expanded shale. I took a chance on it, and won't go back to hydroton. Landscape yards, stone yards have it.