>Should I be concerned about using chemical additives to drop pH? Is there a >particular additive that works better than others? How about more "natural" >tricks that don't cost an arm and a leg? Is the change in behavior related >to the change in water conditions? You might try a water softener pillow. I use Aquarium Pharmaceuticals pillows and get my hardness from out of the tap at 10 GH to under 3 GH. In the past I have gotten it down to around 2 GH, but find that my fish are just as happy at 3. While this may not be soft enough for those super soft spawning fish (D. filamentosous comes to mind) my other dwarfs seem happy and breed. The pillows are rechargeable and very cost effective. I also prefilter my water with a Britta homemade contraption (yes this is me), but this is just a way to speed up the softening process. Andy samaroo@aracnet.net