Backyard Aquaponics
A place to discuss aquaponics

Final got settle and am able to start on the aquaponics system. I was going to start much smaller with a 100 gallon tank, but I found some IBCs for cheap in perfect condition. At 275 Gallon, they were cheaper than 75 gallon tanks new. I got them last week and am planning on starting to clean them out this weekend. I was told they had chicken food supplements in them from a local chicken farm. Should be easy cleaning I think.

We have a sloped field next to the house where I am planning on putting the system, I think. This would help with some of the elevation issues. We are planning on drilling down with a friends post auger (tractor mount) in a series of holes in a grid pattern. We can then knock the dirt walls between and pull the remaining dirt out by hand. This should allow us to sing the sump tank down about 3.5 - 4 feet. We are going to try to berm the fish tank at the other end.

I'm planning on leveling the ground underneath the totes with gravels for drainage. I'm not sure whether to sink the cage in the ground around the sump tank or if I even need at external support there. I'm also unsure whether or not I need to insulate the system or leave it open. I'm in a zone 7b and we get freezing temps, but often not much below freezing.

Any and all suggestions are welcome.

Hello Greenghomesteader,

Looks like you have it pretty well planned out.

Looking at your layout I assume you are going to build a CHIFT PIST system?

The only thing which springs to mind is the height of your growbeds. If you are putting them on the ground (and there is no problem with that) it can make it more difficult to harvest cause you will need to crouch down for veges such as lettuce - just a thought.

Are you going to run constant flood or flood and drain?

Instead of having your beds all level you could step them down as well. As Arne said you do not want to do to much bending.

Keep your sump out of tha ground more, you have to allow for the heaviest rainfall and then more. Do not want ground water contaminating the sump and back through the system.

Look forward to your photos as you start the hard yakka. Welcome

You will need some sort of external support for the sump, otherwise it will almost certainly cave under the pressure of the surrounding soil. You can bury the cage with the sump, but it is recommended to add some sort of sheeting around the cage to hold the soil at bay. I used plywood, but you could even use fibro-cement sheeting...just don't use anything too soft like poly plastic etc. It just won't hold.

And +2 for raising your GBs a little...get them above knee height, or even around waist height if you are able...

ArBe,

Yes, I'm planning on running CHIFT PIST. I'm going to put in a bell syphon on each bed and let the pump(s) run constantly. I ran some small 5 gallon bucket tests to make sure I understood the dynamics of it, but have not built a full size syphon yet. I built it with 1" pipe for the drain size, but I think I will need something larger for these grow beds.

I have three pumps I've gotten so far cheap but new. The largest is a pondmaster 1500 which I picked up for $60 new in the box. I got two Pond Master PMK1250's as well.

http://www.amazon.com/gp/product/B004LO ... YGSD9JNKXY

http://www.amazon.com/gp/product/B0002A ... os_product

ccBear,

I have it at about 3" about right now and I'm planning on coming in about 8" before I cut the hole in the top. I want to retain as much strength as possible. I may not be able to get down that low with the auger. I had not thought about contamination from rain, so maybe it's a good thing.

Ghengis,

I was thinking about cladding the cage in some scrap sheet metal. I think I can get some easily enough. Even coated, I'm worried about rusting though.

I was actually worried about getting the too high and having to reach. They are 24" tall, so I figure at the bottom it will be about 30-36" off the ground. I could plant tall stuff where the beds are lower to the ground (tomatoes?) and short stuff where the bed was higher (lettuces).

That should be fine. I use 20mm (a bit smaller than 1") for my 500 litre growbeds.



What head will you be pumping at? The figure of 1500lph will be at 0 head. This may not be a large enough pump.

I guess it will depend how much the water level drops in the sump. I haven't figured out how much water could be in the grow beds. I'm guess if they all filled up at once the it would be about 20% water and 80% rock. I don't know though I guess if it goes higher than that I need to start rethinking my set up. I have a local source for expanded clay which I think I am going to use. They can load it bit the cubic yard.

I'm guessing worst case it would be a 8' head I would have to deal with. I was already thinking of running multiple pumps, but I wasn't sure. I'm guessing with a lot of flow I would need to run an extra large overflow line. At that height, the 1500 should get about 80GPH, and the PMK1250 will have almost no flow. If I can get the head down to 6', then the flow goes to 250 GPH for the 1500 and 25GPH for the 1250.

User manual: http://www.dannermfg.com/Store/images/i ... /ZG121.pdf

I got the pumps thinking the system I was building was going to to be about 1/3 the size, but it was cheaper to get the IBCs than anything else short of some barrels. I think I will build a barrel system later as a quarantine tank. The original plan would have only had a head of about 4' on a 100 gallon fish tank. It was just cheaper to upsize the system even if I did have to buy new pumps.

I'm thinking 1700 would would on it's own. I think you want to cycle the water once an hour minimum. With a 275 gallon, the 300 gallons @8' of the 1700 model should work. If I do run a second pump, it should bring the cycle time for the system down to 27.5 minutes worst case.

OK, been searching for days now. Finally found this topic:

viewtopic.php?f=12&t=5164

It looks like one IBC will be just fine for a sump. I would need at least 80% (4*40%*1/2 IBC) of an IBC to act as a sump which gives me a 20% cushion assuming all the beds are flooded before they start draining.

Make certain you reinforce the sides of the sump IBC as mentioned previously.

You probably will need an overflow in the sump in case of rain.

Constant Flood without the siphons would work better for this system.
1. Sump would have a higher and more constant volume and might be useable for fish.
2. Higher level in Sump means that you have less head height to overcome.
3. System would have more thermal mass in the form of water if sump was filled.

Won't matter to the plants. Siphons work well but are not needed.

With constant flow, are you suggesting to start the system running and when the growbeds fill up add extra water to add to the thermal mass? For some reason I was under the impression that with constant flow it was more prone to anaerobic pockets due to the lack of draining.

Or maybe I am misunderstanding, I think with a constant flow system there are small drainage holes on the bottom of the GB and a large overflow at the top. Most of the flow but not all would be going out the bottom and excess would be going out the top.

With Constant Flood the water is always moving and mixing which keeps the water aerated. Probably the fact that most AP growbeds are shallow also helps (2 ft or less).

To start a CF system I would fill the Fish Tank, Sump Tank and Growbeds with water before turning the system on. Once it's going I would top it up because of the pipes capturing part of the initial volume (see bottom paragraph).

In a siphon system you have to plan for the highest and the lowest the water in the sump can go. In a Constant Flood system the water level stays constant (except for evaporation and transpiration) so you don't have to worry about the level as much and you can fill it most of the way.

Depending on how you design your piping you may have to plan for the pipes draining into the sump (and leave that much space in the sump so it doesn't overflow if the power goes out). This probably isn't alot of water if your pipe runs are short. For long runs, if you make the pipes go down and then back up and into the sump, when the power goes off, almost all the water will stay in the pipes - works for growbeds this way as well. Probably would be a good idea to have a cleanout in the line at a low point if you do this.

I wouldn't say they go anaerobic, but you can definitely get dead zones in the water flow of constant flood beds if you don't position your outlet correctly. I've found this can lead to mosquitos laying their eggs in the grow bed if you have large diameter media that they can get between near the edges, and under performing plants near dead zones.... I just ran a distribution pipe across my beds...fixes the prob.

From what I've said it sounds like constant flood is tricky to set up, but it's not. Probably would have kept working fine without adding distribution pipes.

And yes, you are kind of miss understanding. A constant flood/flow grow bed can have as few as 1 outlet, at the height you want the water level at. In most cases it is just a flood and drain stand pipe without the small drain holes at the bottom.

What you have described with the small holes at bottom and big hole at top is a system set up for flood and drain that has been switch over to constant flood. People do this from time to time with flood and drain systems if they have fish problems (more filtration flow). But if you are just planning to go constant flow/flood from the start you would ditch the small holes at the bottom altogether.

With a fast grow bed inlet and the media to deflect running water in all directions constant flood water gets mixed around fairly well. However, if you have a corner of your grow bed a long way away from the line of flow between the inlet and the outlet you may get slow/dead zones.

Leaving the small hole off the standpipe is critical as Dr Luke mentioned. If you don't do this all the water above the hole will eventually drain into your sump and you'll have a flood if you haven't allowed enough capacity to hold it. You can flip the standpipe so the small hole is on top but you'll still have some water drain this way so it's best just to leave the hole off.

Because most of the solids end up where the inlet to the growbed is, anaerobic zones aren't likely unless you are overloading the growbed by having more fish than it can handle(in which case you would add more growbeds). Composting worms in the growbeds are another line of defense against this because they help break down the solids.