| First, it would greatly help if we could have some actual numbers as for the different levels in your tank. Salinity, pH, Ammonia, Nitrates, Nitrites, Phosphates, Calcium, temp...etc.
Secondly, I think it was the wrong idea to actually medicate your fish without knowing what you are actually trying to treat, as a lot of times those medications are supposed to be used as a last ditch effort, and I hope that you medicated in a quarantine tank or some kind.
Do several water changes over the week, but not 50% I would suggest a water change of 10-20%, test your params, and then a day or two later another 10-20% water change.
A skimmer would definitely help.
If you can, try to take a picture of your fish, so we may be able to figure out what the "black tinge" is.
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-Jason- Formerly "JKreef" |