If u want to use it for QT, th best is u remove chaeto, UV and try not to have too much media. Chaeto mostly will die due to medication, UV suppress the parasites and bacteria so might give u a false alarm that the fish is ok and u will stop treatment. Some medication will be leech by the media and make the dosage hard to maintain. Light is optional for fish but I normal don't on it for long until they become stable. U may want to consider a ATO and also increase oxygen exchange.