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:
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!