Calcium, along with carbonate hardness, is the most important factor in the marine aquarium for calcifying organisms such as corals, calcareous algae, mussels and many more to prosper.
There are a few ways to raise the calcium concentration in a marine aquarium:
- Calcium reactor
- lime water method / lime water reactor
- liquid or powder calcium products
Be careful that any change should always be done slowly. In case of magnesium deficiency it is not possible to increase the calcium concentration to the desired level.
Optimal calcium values in a seawater aquarium: 450...470 mg/l at 35 PSU