Recirculating Media Filter

[alextret]

I wonder, why, apparently, recirculaing filter principle is not used in connection with aquaria. (Or perhaps I am whong in this respect).

The principle is very simple: a recirculaing filter pushes water through the media several times before returning it back to the tank. See

http://www.extension.umn.edu/distributi ... D7670.html

I'd like to syphon through several tanks in sequence to simulate a very slowly flowing river, with one of the tanks acting as a sump.

If I do it at a decent flow rate, the syphon tubes have to be very thick, resulting in an expensive and unstable system. If I use the recirculating filter approach by sending only part of the flow pushed through the media out of the sump, it might solve the problem (so that I have both decent filtration and relatively slow flow between tanks). According to my culculations, I could replace water in my tanks once per hour (while in the sump the water would go through the media about 10 times per hour).

[Brianemone]

that would effectively be the same thing as a sump on a sump.

great idea for wanting to have low overflow rate but high filtration

[Tanksman]

But as the pollutants are coming from the tanks not the sump I would think the flow through the tanks would still need to be total volume three times an hour.