My main tank was struck by ich. I had been treating it for 2 weeks with salt and warm water, and all my fish were getting better. I had gravel in the tank, and was already making plans to change it to sand. I did a massive, 100% waterchange, and removed everthing in my tank. I took out the fish, water, gravel, decorations, then refilled the tank. The water, however, was at a much different temperature and salinity than the warm, salt water my fish were in. I asked my brother to help me put the fish back in the tank, but before I told him they needed to be acclimated, he dumped in my bichir and african butterfly. Those two died the next day, after spending the night twitching and convulsing. It was very sad, but lesson learned for both of us