Quote:
Originally Posted by
Roddy Conrad 
Hey, JR, no argument with you on points 1 and 2.
Kitty Litter is a superior potting media for the plant in a combined water garden and fish pond. I have been using it in my practical water gardens where we also keep either Sarassa Comet goldfish or golden orfes. The kitty litter is harder for the fish to uproot the plants, the plant thrive in the kitty litter, and there is plenty of mineral content in the kitty litter to replinish the mineral deficient source water here in the mountains of West Virginia.
While kitty litter is a very poor material compared to calcium bentonite for providing silica and minerals to a koi pon, it is great for potting plants in a combined water garden and fish pond. The problem with using kitty litter broadcast in a plantless koi pond is that the water clarity suffers for quite some time after the charge.
And, of course, it is the silica absorbing and removing impurities from the water that makes the bentonite clay most useful in koi ponds, not the trace mineral content. There seems to be some confusion about that on occasion.
And certainly kitty litter is a superior potting media for the idea of a plant filter system for a koi pond as our good Ph. D. friend describes on his CD.