Backyard Aquaponics
A place to discuss aquaponics

I'm planning to construct a fish tank and several grow beds using pond liners. The 48 inch deep FT and the 40 inch deep 55 gallon sump will be completely dug into the ground and the 12 inch deep GBs will be 6 inches above ground and 6 inches below. I slept thru physics class -- will this work?
Barb

If the fish tank is gonna be dug into the ground, how do you intend to make use of the sump tank? What sort of layout are you thinking, a two pump system just for layout purposes?
Probably not much point in having a sump tank if your fish tank is in ground unless the sump tank is say down hill and makes it easy to drain your grow beds that way.

If you sink the grow beds 6 inches into the ground, then the water level in whatever tank they drain into will probably have a high water mark below the bottoms of the grow beds. Keep in mind you want the top edge of your fish tank/sump tank a little above the ground or alot of dirt, debris, and any water from heavy rain will flow into your system which isn't so good. These two things will restrict the amount of usable volume you have for the sump tank and possibly the fish tank too.

Also, Using liner, if you will be framing the grow beds or the top of the fish tank out with wood, please be sure it's pressure treated or at least very unappealing to termites. I've had some lumber/liner grow beds fail due to termites, they apparently don't notice that they have eaten into the liner from the wood till they are suddenly all wet. I have since gone to using 100 gallon stock tanks for grow beds.

Anyway, if you are doing loop siphons from the grow beds to the sump tank, you might get away with having the top edge of the sump tank above the bottom of the grow bed but only if the loop siphon can drain directly into the sump. If you are doing timed pumping with stand pipes for flood and drain, the grow beds will likely never drain below the high water mark in the sump. If you do continually flooded, this layout may be ok but there can be drawbacks to such operation.

I would advise giving yourself a bit more fall to work with. Like place the grow beds on the ground rather than sunk in. Actually I would advise reading about CHIFT PIST but you probably won't be able to run that way with only a 55 gallon sump.

A little more info about details might help us help you a bit more.

Oh -- the danger of assuming! I thought I totally understood sumps since I have 2 under the saltwater fish tanks. My current sumps take dirty water from the fish tanks [via an overflow] allow the solids to settle where they can be easily cleaned out, filter the water and then pump it back into the main tank. One pump, 1 overflow and gravity do all the heavy lifting.

Seems that in AP, sumps are used in a totally different manner. But couldn't they be used the same way? Just use 2 pumps and add in the GBs?

Back to research!! Thanks JT
Barb

Barb,

As TCL said, things are unclear. What are the relative heights of top and bottom of each of the three containers? I'm probably just being thick...

Not nearly as thick as I am -- I'm totally re-thinking my plan. In the original design the relative heights are probably waaaay too close. I can see now that gravity is a vital componet of most systems. I'll draw up new plans and be more specific before I post them.

Thanks!
Barb