This is the inside of our 1800 square foot greenhouse. All of the tanks and filters are DIY (Do It Yourself). The first four I built eight years ago. Since I built those filters I've made a few adjustments to improve the efficiency. The tanks will hold 1,000 gallons. I use Pondmaster 1200 gph mag drive pumps for each tank. My water source is from a well on a ridge above the mud ponds. I use it to top off the mud ponds during long dry spells, to refill ponds after I drain them and to supply the water for the tanks in the greenhouse. The two tanks at the back left of the greenhouse are used as reservoirs to aerate the water and let it come up to the same temp as the other tanks before I do water changes.

The large pipe running down the middle above the tanks is connected to a Gast blower that can run thirty six inch air stones. There is a 3/4 inch tee to each tank with a ball valve to control the air flow. The electric is run through 3/4" PVC conduit pictured below the 1-1/2" air supply pipe. There are two circuits and each has a GFCI. This keeps all the air hose and power cords out of the way.

We are currently setting up eight more holding tanks on the outside of the greenhouse below the dam of the first pond.