Totally new to this, but built same E/F system with some slight changes in looks. You should have no water remaining in the system after the pump stops and starts to back flow. It should drain entirely. Really curious how any water can remain in there.

I'm putting together what I think is a dank grow room right now... looking forward to my tomato seeds getting here in about a week to start off.

Fix your E/F system so no water remains or you will have issues with either root rot, or something growing in there you don't want.
HydroDynamics Reviewed by HydroDynamics on . Hydro ebb/flow flood schedule opinions/theories Ok Ok, there are many factors that affect the best flood and drain schedule. Some set-ups would require more frequent floods than others. Some strains may benefit from more or less frequent floods. Root space, aeration and air-flow, use of C02, strength of nutes, grow medium type, these are all things that determine best flood schedule. I want everyone to give their opinion on this. Tell us YOUR success you're having, your grow medium, your flood schedule dark and light. I use Hydroton, Rating: 5