My 65 fowlr is doing well except for sand sifter fish...lost 2 jawfish about a month ago...just lost my diamond goby this morning...he had been QT'd for at least a month at a reliable lfs...my guess is that my sand bed does not have enough good stuff in it to maintain them...also I have eggcrate under the bed...don't know if this is a problem....the goby had what seemed to be a dark blood spot behind his mouth as he lay dead...any ideas...