Hi everyone! I'm new to this thread and I'm looking for some answers on how to control purple algae growth. I've had my saltwater fish tank set Up for over 2 years now with constant algae problems. It began with green and brown algae. Now it's mostly this hair like purple algae (slippery, not hard), which has spread all over my rocks, sand and glass. Any help would be appreciated! My tank is a 55 gal and I try to keep the lighting with 8 hours normally and at night I use a blue lighting. Any there any types of fish I could buy that would eat the algae?