- 1). Introduce a live rock into your aquarium that has existing purple coralline algae on it. You can get these live rock samples from friends that have the algae already present in their aquarium or from online retailers.
- 2). Allow a blue light to shine into the aquarium. Purple coralline algae are supported by blue light, which mimics the natural light of deep ocean conditions where purple coralline algae thrive.
- 3). Test the aquarium weekly for nitrate and phosphate levels. Always maintain low levels of nitrates and phosphates in the aquarium, as these nutrients support other algae that can easily take over the purple coralline algae. Phosphate levels should always read close to zero and nitrate levels should always be less then 10 parts per million.
- 4). Complete a partial water change weekly to keep nitrate levels down. If the nitrate levels tend to stay high, more frequent water changes should be completed.
- 5). Supply the aquarium with a calcium supplement. Coralline algae are similar to coral when it comes to calcium. Both need sufficient calcium to grow well. The aquarium should have 400 parts per million of calcium to grow purple coralline algae well. Conduct a test weekly to determine calcium levels. Salt mixes for aquariums usually contain proper calcium amounts, but if the test shows that calcium levels are low, adding a supplement will bring the aquarium levels up to par.
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