more water changes... algae is a sign of water perameters being off. likely your nitrates are too high and possibly phosphates from either inadequete water changes or naturally high phophate water. Live low light plants such as crypts ime are a great way to keep algae minimal if not non-existant.. and of course there is always a lil' elbow grease and filter floss, or a magnetic scraper..
in a nutshell... ime none of those products are fish safe let alone scaleless fish safe.