Hi Guys, my Bruce all of a sudden died overnight! I dont know how this happened as his PH was 7.1 and nitrate/ammonia 0. The temp of the tank was 21 degrees. He was eating well and active and everything - he seems quite happy. He wouldnt have swallowed any stones cos he only has huge pebbles in his tank and some plastic plants. I have no idea what could have happened! I feel so terrible!