I have a fully cycled 55 gallon tank. I syphon the gravel, do partial water changes and clean the tank walls once a week because I like my tank to look perfect and my fish to be healthy. I only keep the lights in tank on about 6 hours a day and the tank is nowhere near direct sun. My problem now is brown algae. I must clean it off of my plants every day and it's back within hours. It's not as bad on plastic plants as it is on some of the plants that are a silkier, more natural looking plants. My water parameters are perfect and my water is clear and I don't overfeed but the decos just look gross. Even my fake corals are getting taken over with brown spots. I do not want to get a pleco or other algae eating fish, my tank is already fully stocked. Is there anything that I can use, preferably not a chemical, I heard these easily kill fish? Or something you can suggest without keeping my fish in perpetual darkness that will do away with this brown algae? Thanks.