Koi Toilet Bottom Drain, Tetra Bottom Drain, Retro Drain

Click on Picture of this air pump to go to the Air Pump Page.

Air pump to run Two Rhino Drains or any Bottom Drain with an Air Difuser.
For air drain... the size of the air pump is a function of the depth that the drains are set.
A good rule is "20lpm per meter of depth".
Examples;

1 meter = 3.3' = 20 lpm for one Rhino Drain--Double the depth for Two Rhino Drains.
2 meters = 6.6' = 40 lpm for one Rhino Drain--Double the depth for Two Rhino Drains.
3 meters = 9.9' = 60 lpm for one Rhino Drain--Double the depth for Two Rhino Drains.
4 meters = 13.2' = 80 lpm for one Rhino Drain--Double the depth for Two Rhino Drains.

Now then, if he runs two air drains, you need to double the depth.
For example;
2 drains, each at 2 meters = 4 meters total = 13.2' = 80 lpm

Small Retro Drain

Easy Installation/Minimum maintenance Handles high volumes of water For ponds 500 to 1400 Gallons.

Multiple option pipe sizes 1/12",2",3" , 11" Diamtere x 5" Height

Balanced water celocity entrance rate, Burable ABS plastic construction.30% Smaller than Large Retro Drain.

Suggestion on installing the Retro Drain. Take a white plastic meat board Place the retro drain in the middle of the meat board. Drill holes in the legs of the retro drain and down thru the meat board. Take Stainless steel bolt and nut and attach the retro drain to the meat board. You may also want to find a stainless steel pipe band to attach to the pvc pipe to the meat board also so it will not slip out of the retro drain. Also prevents the suction of the water thru the pvc pipe when pump is on so that the liner doesn't get suctioned up.

Installing the Retro drain on top of the liner of the pond to the pump.

Installing a Retro Drain in a Show Tank.............................. One of the safety factors is that if water escapes from the tank there will still be 4" or more water left in the tank for the koi.