Feedback on planned system design?

[Daniel]

Hi all -

New to the community here and wanted to run my system plan by you experts for feedback before I jump into the world of aquaponics. I've just finished reading Sylvia's book which I thought did an excellent job of distilling the vast amount information about aquaponics onto the printed page. However, I'd like to avoid as many rookie mistakes as I can - so I'll appreciate any feedback on my plan that you can give me.

 

I already have access to an IBC tote and a number of 55 gallon drums. I also already have a 10'x12' greenhouse to install my system into. The greenhouse is not heated, and only has a single sheet of plastic covering, so I'm still evaluating my options for upgrading my greenhouse into something I can heat, or shutting the aquaponic system down for the few cold months here. (I'm in Memphis, TN so Dec 1 - March is likely too cold to grow most plants inside my current greenhouse).

 

My planned system is to use the IBC tote as my fish tank with the top 12 inches cut off for a media based grow bed. I plan to use the CHOP system with a 55 gal drum as a sump tank, and another 55 gal drum cut lengthways for two additional media grow beds.

 

My concern here is that I have not calculated yet whether one 55 gal drum is a large enough sump tank, or if I need to use two drums piped together to hold the volume of water required for my growbeds. I'd like to use autosyphons on each grow bed in order to leave the pump running continously. I thought to reduce the max water burden on the sump tank I could have the IBC tote grow bed overflow to the two 55 gal drum grow beds so the 3 beds are never all empty at the exact same time. Would this create issues for the 2 growbeds filling up too quickly? Perhaps I'll end up creating more issues than I'm solving by trying to simplify the sump tank into 1 drum?

 

I'm also planning on burying the sump tank (the 55 gal drum on its side), and partially burying the IBC tote (fish tank) in order to help keep constant temp year round. Not sure yet how far I can bury the fish tank, since I'll need gravity to feed the grow beds below the top of the tank.

 

I'm not a very good sketch artist or I'd upload a picture of my planned system. Let me know if you need any clarifications before offering advice, otherwise I'll appreciate any pointers!!

[Daniel]

TC - just saw your response. I realize I will need to use a large pipe between the barrel grow beds and between these and the sump tank in order to keep the sudden inflow of water from overflowing these beds. Also, I thought by putting the barrel grow beds in series after the first grow bed I could have a constant flooded bed without much issue of solids build up on plant roots since the solids would be caputured in the first (larger) grow bed - is this just newb thinking?

If I split the SLO pipe coming from the fish tank into three directions to feed each bed directly, and then have each bed directly drain back to the sump tank, solids would not be an issue with a constant flooded bed? Do you think dropping the water down into the bed would provide the aerated water these beds would need, or do I need some extra bubblers to do this successfully?

[TCLynx]

I always add some extra aeration of some sort into my fish tanks even if it is just for backup in case of water pump failure.  It usually keeps my fish eating better even during really hot weather too.

If you have your water fall a distance to the lower grow beds, that could help aeration but you will need to do something to deal with splashing since most plants hate to have their stems constantly wet and having too much of the surface gravel always wet is often problematic.  I would just use a larger pipe as the splash down shield and have a ball valve to feed each grow bed from the flow out of the fish tank.  I would recommend spreading the solids around among all your media beds rather than to just one bed.  (ya know that splash down pipe could also have some filter media or scrubbies inside it for added solids filtration if you like and guess what?  Worms will happily live in filter media or scrubbies and eat that fish waste and provide worm wee to your plants.  Heck I suppose you might even use a zipgrow towers as the feeds to your lower beds if the heights are right but it would require more than one tower per barrel since you can only send so much flow through a tower at a time.

[Daniel]

Just got both your replies TC. I guess I'll reroute to each bed from the fish tank as you suggest. It makes a lot of sense to not have to redo everything if I have an issue with only one bed. I was planning on extra aeration in the fish tank too, though I didn't know if a flooded grow bed needed aeration separate from the fish tank aeration. I think you are saying that having enough aeration in the fish tank is the primary thing, and having extra aeration into the beds can't hurt (as long as I limit splashing). Did I catch this right?

I'll figure out about the splash down idea once I start laying out the system and figuring out how much vertical distance I have to work with.

Still planning to start cutting the tote and digging the foundation area on Wednesday... I'm looking forward to getting started, and continue to appreciate the feedbank - "in multitude of counsellors there is victory"!

[TCLynx]

Sounds about right there Daniel (and a splash down pipe full of scrubbies for both the barrel beds will provide some extra filtration as well as solids filtration.)

Keep in mind that you can only stock the fish tank to your grow bed capacity.

[Daniel]

OK - so updated rough sketch is attached. Since I'm no longer trying to balance siphons for the barrel beds, I went back to thinking of cutting the barrels lengthwise. Since I believe flooded beds work best for greens which don't get that large, I'll have more growing surface this way. The comment about stocking fish to grow bed capacity is point well taken, but I'm assuming this setup gives me adequate bed capacity for normal 1lb of fish / 5-10 gal of fish tank?

[TCLynx]

Much better, one last thing you need to add in though, A T and a Ball valve to allow you to spray any excess water back into the sump tank. You will wind up needing to adjust the ball valve to the IBC bed so that the siphon will work and you may need to close off one of the valves to the barrel beds so that the other will get some flow and if by doing that, you reduce the flow out of the fish tank to less than the pump can send in, you will then need to back off the flow from the pump by diverting some back into the sump tank with a bypass, basically a T and a ball valve that when opened will send some of the pump flow back into the tank with the pump.

[Daniel]

Thanks again TC! I'll be sure to build an overflow valve directly back to the sump tank as well.

I'm going to pick up my tote today and plan to cut it and the barrels so I can arrange them in the greenhouse in order to make a list of everything I need to buy - wood for frames, pipes, fittings, etc...

I'll try to post some pictures on this thread later, in case anyone wants to see how things turn out.

[TCLynx]

Definitely, people love pictures

[Daniel]

Update - got my tanks cut yesterday (see picture). Started working on frames for the growbeds, but didn't get this finished yet. Thought I'd post a picture of my tanks arranged roughly according to how I plan to install them into the greenhouse. The sump tank (55 gal drum on right side) will be buried, fish tank will sit on top of ground (as is) and the grow beds will be framed up to sit a little off the ground (to leave room for drain pipes), but still below the top of the fish tank. I'm excited to see this project progressing, but I still have a long way to go!

[TCLynx]

Be sure to put the IBC back in the cage or frame up supports for it as well since the plastic will bow otherwise.

[Daniel]

yes - thanks. I had it out for cutting and cleaning, but I'll put it back in the metal frame. Once I finish getting everything installed with supports I'll upload another picture. Hopefully this weekend I'll have time to finish this phase so I can start on the plumbing.

[Daniel]

Another photo update here after a little progress today on painting the fish tank and grow bed, and assembling on location. Now just need to finish digging a the sump tank into the ground, and start on leveling the beds and plumbing the system. Not sure how long this will take, but hopefully next update will be in the Member System Introductions area!