Backyard Aquaponics
A place to discuss aquaponics

I vary pumping times quite regularly. If a system gets a bit of an algal bloom I turn the pump on permanently and run it for a few days and or weeks till it clears up.

My original corrugated iron system at home still runs on float switches, no timers involved. It pumps only about 1/3 of the fish tank every hour, yet has successfully grown many different fish, including a big crop of Barra.

Maturity of a system is such an important factor, that system is 4-5 years old now but I've had it only lightly stocked for a while with probably about 20 decent size silver perch. The power has been going off quite a bit recently in my area as they are having major electrical problems and my system has had periods where it's not been running for days. Fish are fine, perfectly happy in a 2000L tank without any pumping. Not that I'd recommend it.

The 15/45 timing cycles that we recommend is for the purposes of standardizing in our systems. We find it works well with our systems and it keeps it simple for people to understand. This doesn't mean it's the only way to do it, or even the best way for a particular system.. We often run the little balcony systems at 30/30 because the growbeds are so small they tend to drain pretty quickly.

Thanks for your input Joel. Looking at possibly putting another one or two 6mm holes in our GB drains to decrease drain time and possibly even go to 15 on 15 off to get 100% plus of the water in the school system turned over each hour over summer while we have no proper shade structure over it. Can you forsee any problem with this?

I wouldn't bother increasing the holes in the standpipes, just increase your pumping time to say 30/30.....