Magnetic thing every few days, and when the coralline gets bad I use a rasor. Im with Bruce, the water turns all pink, and it looks super clean the next day,

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15 Gallon Nano, Current USA 80 watt PC Light, Pengiun HOB Refug, Pair of clowns one ocellaris and one purcula!
100 Gallon Tek T-5 Fixture 6 Bulb, Algea Forest!!!