How to Remove Red Algae From a Fish Tank
- 1). Physically remove the algae with an aquarium scrubber pad.
- 2). Perform regular water changes. Using RO or DI water will ensure that nutrients are not added to the tank. Algae need nutrients to grow. Also, use a gravel vacuum (an wide-mouth siphon) so you can clean the gravel as well.
- 3). Cover the tank in plastic bags for several days if the problem persists. This will block out all light and kill the algae. Do a water change immediately afterwards, as the dead algae can rot and foul the water.
- 4). Add specialized filters if the problem continues. UV sterilizers and diatom filters can kill and filter out algae in the water column.
- 5). Consider an algaecide, as a last resort. Follow the manufacturer's instructions to the letter. Algaecide is toxic to plants and invertebrates, and not particularly healthy for fish either.
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