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     Ok, so its spring time and I've started building my system!  I've been building this thing for a month now, and it's still not ready.  What the hell was I thinking!!! Back breaking labor and $1k in parts and supplies!  This must be an addiction.  I'm just glad my wife doesn't realize how much I've spent on this little project.  If she ever figures it out, I'll be sleeping in my grow bed!

     Ok, ok.  Enough whining.  So here's the update,  I've laid the gravel bed where I'll set up the system.  The FT and GB are built and set up on cinder blocks.  I used .6mil plastic for the liner in both.  I put a double layer in the fish tank.  I was going to double layer the GB too, but I ran out of plastic.  I've gotten all the plumbing in.  I went with 1/2 inch pvc for the FT and GB.  I found this neat little round lawn sprinkler that I set up to provide aeriation (did I spell that right) in the FT.  I put in a 2 tier waterfall that I picked up and I'll be setting stones around it later.  So I'll have 2 points of oxygen input in the FT.  I used 1 1/4 inch bulk heads and pvc for the SLO into the sump tank.  I used 2 55gal storage totes as my sump.  I plumbed them together with 1 1/4 inch bulk heads and pvc.  I had to go with that size because that was the largest fittings I could find in the area.  I have a bell siphon which drains into 3/4 inch stand pipe.  I wanted to go bigger, but again that's all I could find. 

     The siphon kicks on, but I don't know if it shuts off.  I had to stop filling the GB when I realized I hadn't washed my media well enough.  The water started turning red!  So I now have to drain it out.  Yay. I've washed 19 40lbs bags of red lava rock.  I hate washing gravel.  Only 43 more to go!  Did I mention that I hate washing gravel.

     So that's where I'm at so far.  I'm totally stoked to finally have it built.  As soon as I get more rock, I can start cycling!!  So everything is on hold until payday.  I put the system stats below and as soon as I'm finished loading rock in the grow bed I'll post some pics.  If I wasn't so tired I'd jump for joy.  So I'll just give a thumbs up instead, 

OWW! OW! ow!  My thumbs are too sore.  Did I say how much I hate washing gravel yet?


Fish tank: 7’x3’x32” with a 2’ water level = 314 gals.

Grow bed: 8’x4’x1’ with grow media and bell siphon

Sump: 2 55 gallon totes plumbed together

Pump:  ActiveAqua Pump 550 GPH

Grow Media: red lava rock

Constant flow  flood and drain CHIFT/PIST

Sun shade and cover for the fish tank

Thanks for the comments.   I was kinda loopy  when I first started this blog, I keep staying up late to research AP! (sound familiar?)  So my blog is officially updated.  Ta Ta for Now. 


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Comment by Jake Schneider on April 18, 2012 at 2:53pm

Hi Benjamin, 

For the liners, I used .6mil plastic that is used for drop cloth in painting.  I know, I know but I'm cheap.  I can get twice as much of it for the same price as EDPM.  If I bought EDPM, I'd still be in the planning phase.

Comment by Benjamin Smale on April 18, 2012 at 1:50pm

I feel your pain. I'm currently building my first system as well, and hate washing gravel as well.  I don't know if I like your choice in liner, is it PVC?  I'm using an EDPM liner instead of PVC to avoid the chemical leaching.

Comment by TCLynx on August 17, 2011 at 9:26pm
If you use bell or loop siphon shouldn't be based on space used in the grow bed since either type of siphon should have a gravel guard around the drain to allow you to access the drain inside the bed to deal with roots or whatever so you will still need a gravel guard around the drain.
Comment by Vlad Jovanovic on August 17, 2011 at 7:05pm

Hi Jake, 

I'm going to avoid giving you any definitive answers and leave that for people who are much more knowledgeable and have direct experience (I am in early build-phase), so don't take this as gospel...

A 10'x4'x1' media bed will have a total volume of 299.23 US Gallons (lets say 300) so you can expect to need around 40% of that to flood it with water, which is almost half of your fish tank volume. A sump might be a good idea, especially you want to grow out your fish to a decent size. (which you may have a hard time doing at under 24" of water).

And yes, as I understand it catfish and talapia will do just fine as long as the difference in sizes doesn't allow one (any) fish to prey upon the other.

If you are sure that you want to go with a bell siphon check out these links:


You may want to check out loop siphons, as they don't use up valuable grow space and are really easy and cheap to construct. (I made a mock-up size set up in the garage in about 10 minutes that worked like a charm). You probably just want to make sure that whatever tubing that you are using for your loop has a decent wall thickness so that it doesn't collapse over time.

If you use the bell siphon you may want to stick with a 1" size but ultimately that depends on your design.

You might not want algae in your system as it uses up valuable oxygen as well as nutrients. You may want to grow algae or duckweed in a separate tank not connected to your AP set up.

The general rule of thumb on stocking densities (found in the "General Rules of Thumb" page) is one pound of fish for one square foot of grow bed about 40 lbs

Make sure whatever you grow bed or its liner is made from can handle the jagged lava rocks.

Dog food might not be so good? Rovers digestive tract might be a bit different than Tally's or Barra's or Yarbies'...Check out the ingredient list, corn (not corn gluten which is easily digested by fish) and other grains may be difficult for fish to digest, and it will probably increase your ammonia levels plenty. But, hey if your feeling lucky, experiment... :)  I know that Koi, while omnivores are unable to digest any animal fat or dairy products properly. Over time, this fat gets deposited inside the gut cavity between the organs, which then cannot operate properly, finally resulting in what is known as Fatty Degenerative disease. I don't know if this is the case with talapia or catfish so you may want to research this a bit. (Or maybe someone who has tried might chime in). But if you are spending the time and money to build the system you described, you may just want to fork over the cash for a decent and well balanced diet for your fish. (And ultimately yourself)... Besides, the quality of your fish food will have a lot of bearing on how your plants do.

Breeding colonies I have no idea about...but I'm sure that someone else will help you out with that one. 

Again, all of the above should be verified, and is based solely on research and talking with others. So no direct experience on my part. Hope that some of this helps anyways... 

Good luck with your build...its nice to see that someone is thinking about aesthetics! 






Comment by TCLynx on August 17, 2011 at 5:44pm

Lets see, don't base you number of fish on the fish tank size.

Base the amount of fish on the grow bed size.  For a first season system I would start out with one fish per cubic foot of grow bed so that would be 40 fish with a planned grow out to 1 lb.  (catfish grow bigger so in my big system I will often stock less fish.)


Lets see so your grow bed will be just under 300 gallons total so you could be fluctuating your fish tank by almost 40%.  If that seems too extreme to you then you will probably want to run with a sump tank.  I would recommend a sump tank of 175-200 gallons depending on how low your pump is able to manage to pump down to.  Or if you want to add more grow bed later, I would recommend having 300 gallons of sump tank.  In general people kick themselves for going too small on a sump tank.


1-Plumbing size is based on flow rates so we need to know what pump you want to use to help you there.  also need to know if this is going to be grow bed draining to fish tank or if it will be Constant height in fish tank pump in sump tank or what?  Is the waterfall going to be running from the same pump as the grow bed? 


2-For the bell siphon I would venture that 1" stand pipe would probably work but if you were to use a 1 1/2" uniseal or bulkhead you can then use a reducing bushing to put the stand pipe in and be able to easily get it out to make adjustments if needed.  I recommend looking up the Affnan siphon.  Make sure your gravel guard lets you access your stand pipe and siphon parts easily and make sure it allows the water to flow though very freely.


3-Tilapia and catfish can coexist but there could be some interaction between them at times that could be a problem depending on the density and breeding actions of the tilapia.


4-For your first season and cycle up, I would block most of the light from the tank since algae can cause a new system problems.  Later on you can experiment with how much light you can let at the tank without causing you problems.


5- You should only stock as much fish as you can provide ample aeration and filtration for.  Temperatures can affect this so shade for your system the first summer will be important till you see how your fish do.  Anyway, A good starting point for stocking of a new system will be 1 fish per cubic foot of grow bed (would be 40 fish based on your plans above) with a planned grow out of 1 lb each as long as you are filtering the volume of your fish tank each hour.  After you get comfortable with the fish keeping and the way your system works you will be able to adjust your stocking to balance your system for your needs.


6-There is a tilapia breeding group you might want to join to get details on that.


7-I don't expect that dog food is going to be formulated for fish nor is it likely to provide a good balance of nutrients for the plants and I would expect some water quality problems from using it.  Also, most dog food is going to be way too big for tilapia to eat and the catfish probably wouldn't go for it till they get really big too.  I have heard of some people feeding catfood to their fish but I'm not sure I would recommend that much either though I've never tried it.


Keep reading and get a test kit to experiment with your source water and be ready for cycling up your system.


Be wary of using liner near wood in termite territory (this is a mistake I made.)

Wash lava rock well before using it in the system to get rid of dust and clay which could affect pH long term.  Rise the clay balls to get rid of the oxides that could spike pH at first.

And I highly advise fishless cycling.

Comment by Eric Warwick on August 17, 2011 at 5:30pm
Glad to hear your addicted.  Questions, however, are generally in forums--the thing above blog posts--because it's easier to answer questions and people who have the same question can go through them easier. Hope to see you more on the forum. 

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