VERY important question! When people with ponds refer to using kitty litter, it is ALWAYS the Non-clumping kind, and no scents. In other words, the cheapest you can find, PURE CLAY. I've had a hard time finding it everywhere, but my Wal-Mart (and others say it is still available at their W-M) has Special Kitty, plain, pure clay, no scent. It's in a blue and red/pink bag. If you get the clumping kind, it gets really slimy. Yep, I messed up once and got the wrong stuff. Yuck! The pure clay is used because it is heavy (unlike most potting soils which would float and make a mess) and it stays in the pot. If you are planting something that is going on the bottom or on a shelf in your pond with fish, might want to put some rocks on top of the clay, especially if you have koi that like to dig things up! I never had problems with my koi until this spring, and they dug up one freshly planted lily. They didn't eat it, just either got caught swimming through it or simply yanked and it came out. Just repotted it and used more rocks to hold it in better.
