my flame angelfish recently died. im not sure why i noticed his tail was fraye a bit but i thought it must be the bue tang that i got with my 210 gallon set up. i just recently found a disease called fin ad tail rot before he died he seemed fine and was eating and wasnt lethargic could it have been a natural death not from disease. i just want to mke sure it doesnt happen gain to any other fish i get in the future