To avoid mold and root rott, completly light proof your water area, some even duct tape the air lines, and water temps under 70D, some get up to 72, but I think that those temps are pushing it a little. Air stones should be cleand with peroxide and water, you can put in a bowl with the air stone and run the air pump threw it, I just leav it over night, but the stones are so cheep, you should replace them IMO if you think that they are a problem this time around. Hope this helped some
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