An Editorial About Bottom Drains by Tom Burton as reprinted from the magazine of Mid-Atlantic Koi Club

They’ve just discovered an eleventh stone tablet somehow missed by Moses. The inscription reads, THOU SHALT NOT BUILD A KOI POND WITHOUT A PROPER BOTTOM DRAIN. Imagine that. Even then they knew. The ideal set-up is to have the drain(s) CONTINUOUSLY gravity feeding to the filter system(s). Why gravity feeding? So the big stuff stays as much intact as possible as it enters and settles in the first phase of the filtration system, appropriately called the settling chamber. Why continuously feeding? Because crud lying static in the bottom of the pond and in drain pipes waiting for someone to purge it, quickly becomes anaerobic (lack of oxygen), starts producing that sulfuric or rotten egg smell, and poses a dire threat to the health and well-being of our treasured friends. This becomes even more acute during the winter if the filter system is shut down. Why? Follow this line of reasoning: If the water is not being re-circulated and stands relatively still, where is the worst water in the pond? AT THE BOTTOM. Where do fish stay in the winter? AT THE BOTTOM. If we don’t run our systems we force the fish to live in their own, continually worsening sewer. No wonder so many folks dread deadly Springtime. AND, to absolutely compound matters, starting up from scratch each Spring means all the pain and agony of A New Pond Syndrome every year. Ugh!! They say it takes a couple years for a biological processing station to become mature and although arriving at that conclusion was not done scientifically, experience sure bears that out. And as the water warms and we start and then gradually increase feeding, the filter is ready to react on demand as opposed to going through the tenuous ammonia and nitrite cycles/spikes on its way to kicking in. One last thing: a minimum of four inch drain pipe from a drain similar to the one on page 32 of the Tetra Encyclopedia of Koi, is still the state of the art (though a new drain from the UK that incorporates aeration shows great promise as well). Even a four inch pipe will need to be cleaned out from time-to-time after about the fourth year of use as crud grows on the walls and really slows down the flow.

There. I feel better now that I’ve gotten that off my chest (again).