Can a dwc double as the sump?

[Josh]

Hey everyone,

Im getting ready to re-do my flood and drain mixed media system due to the fact that I want to expand the DWC area and because I dont like the fluctuating water levels in the fish tank.  

I want to add a sump to the system but space is an issue. Im wandering if anyone uses their DWC as their sump tank.  If there was enough water in the DWC, would the changing of water levels bother the plants?

I would like to continue with the flood and drain method so my idea is the following:  With the dwc as the  low point in the system and the fish tank as the high point, the dwc water is pumped up into the fish tank which overflows into the media bed and then back into dwc.

I feel like this should work, but am I missing something?  

What do y'all think?

Thanks,

Josh

[Harold Sukhbir]

Hi Josh,

Of course that works!.If the DWC has a larger capacity than the FT the levels in the DWC won't fluctuate dramatically enough to cause much concern. If however the volumes of FT and DWC are close to each other the movement in DWC will be more severe. If you are still concerned with fluctuating water levels you may consider attaching an activated charcoal fixture to a small side mounted plastic toilet float in either the FT or the DWC. A small filter will remove most of the chlorine from your tap water and at the same time maintain your standard water levels.

[TCLynx]

As long as you are not fluctuating the water levels enough to mess with your air stones too much or cause plant roots to be sucked into the pump, I don't think the plants will notice a couple inches of rise and fall.  To keep the fluctuating water levels from really messing with air stone balance, you may really need a seperate air pump for the DWC beds so that your fish tank air won't vanish every time the sump is a tad low.

[Don Luttrell]

Hey Josh, that sounds very similar to my system. Everything overflows and my pump runs out of my last grow bed. 10 inches deep. So it works. The only issue i run across are roots getting into the pump. But you can cage it and put a prefilter around the pump to avoid that. May need to clean it from time to time. 

How big is your pump? Do you know what your flow rate is? How is your flood and drain working... auto-siphons?

Doesn't' sound like you are missing anything.