420 Magazine Background

Cheap DIY fully automatic E&F with no electronic timers or mechanical pumps?


New Member
Hello everyone! I am hoping to get some feedback on my first ever hydro plans. Im in the final weeks of my first MJ grow in soil and its going pretty well. I have decided that I want to try a hydro grow next time around.

I think I have come up with a cheap, easy DIY, fully automatic ebb and flow setup that uses no timers or mechanical pumps - just an air pump.

After tons of reading, I have decided to try an ebb/flow setup with two plants in scrog. My grow tent is roughly 7 sq ft (28"x38"x48"tall) and I have a 300 watts LED light fixture using 3500k Solstrips (the same led's as in Quantum Boards).

I have read a ton of threads and one common problem is heat in the rez from submersible water pumps. In order to reduce the heating problem, I am going to use an air driven water pump (air lift pump) instead of a submersible, mechanical pump to do the flood/drain cycles. I can mount the aquarium air pump (that runs the air lift pump) remotely and cool it with a fan, if needed, so hopefully I wont have heat issues.

Im going to have two interconnected 5 gal totes as grow buckets filled with hydroton. They will be connected in series with the water entering one and draining from the other one. The rez is going to be another 17 gal tote with at least 3 DIY air stones. It will be under the table the tent is sitting on.

Im going to try Mega Crop for nutes.

Attached is a rough sketch of the layout. I have done some 'wet' trial runs and it takes roughly 15 minutes to fill and about 3 minute to drain using the automatic siphon — no electrical timers needed. The air lift pump runs full time. As soon as the 5 gal totes get to the preset fill level, the siphon trips and drains back into the rez and the cycle starts all over. Those times are based on just water in the totes. I haven't tested with them full of hydroton, so the final times may be a bit different, but I expect the same ratio of fill time to drain time. I can adjust the fill and drain times by tweaking the siphon and air lift pump rates, so there is some flexibility. So far, I have extended the fill times to a little over 30 minutes with the same 3 minute drain time. It looks like my shortest fill time is going to be around 10 minutes.

Anyway, I love to get some feedback, advice, suggestions, criticisms, raspberries, etc. A lot of my reading and research has been on this forum, so I already owe you guys a bunch of thanks!



Member of the Month: May 2009, Oct 2010, Sept 2017
Member hasn't visited the forum since February, 2018.
Top Bottom