How to Clean Black Algae From a Hot Tub
- 1). Climb into the hot tub and scrub every visible piece of black algae with your wire brush. Continue scrubbing until you have torn away the hard outer shell.
- 2). Fill your bucket with water from the hot tub. Pour in the shock mix using the formula of 1 pound for every 10,000 gallons of water. Adjust the mixture accordingly if you have less water in your hot tub.
- 3). Pour the shock mixture into the hot tub and turn on the filter to circulate the chemicals.
- 4). Let the hot tub sit overnight. Brush the walls down again at least twice the next day. Add the metallic algaecide to the hot tub after the second brushing.
- 5). Brush the hot tub once a day for the next four days. Add another shock treatment to the hot tub at the end of the sixth day.
- 6). Brush the hot tub for three more days. Add one more dose of algaecide to the water. This should be sufficient to eradicate the black algae.
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