Calcium
Calcium aids growth of purple, pink and green calcareous algaes, snails, hard tube worms and clams. Corals will open more and stay attached to their skeletons better, with regular use. If overdosed, the high pH of the limewater will rapidly convert much of the bicarbonate in the tank to carbonate, increasing the likelihood of precipitating calcium carbonate. Also, addition of solid lime particles can cause local extreme spikes in pH and calcium that nucleate precipitation of calcium carbonate. However, this rarely causes lasting harm to tank inhabitants (at least that has been recorded to date).
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