what type of system do you have, if it is fo 50 is not leathal for fish only, but water changes can help
what type of filtration do you use
what type of substrate and how much
how much livestock
how old is the tank
did you recently add fish, and how fast have you been adding them
do you have any lr
do you have a skimmer
how often and how much do you do water changes
and your water source, has it changed, or been tested for nitrates
these things may help us to help you more than just guessing
[ December 20, 2001: Message edited by: fshhub ]