I bought a bag of Kodak Pro powder fixer, I was mixing it in the bottle at recommended temperature, and for the most part it dissolved but there are a few hard chunks of fixer that didn't dissolve. I tried breaking them up and while they crumbled they did not dissolve. Do you think it is still usable? Now that I think about it, the fact that there are some small, hard pieces in the solution is a problem because if it got in the tank they might scratch the film. Oh well. I'm still baffled as to how this happened, my temperature was certainly correct. The 1 gallon jug was only about half full of water though, maybe that was it? I think I might just go with the liquid solution next time. edit: Also, if I end up tossing this fixer (which I Imagine I will) is down the sink okay, or should I find a more "environmentally friendly" way?