FAQ: My calcium level won't change using Seachem Reef Calcium™! How do I get it to budge?

Reef Calcium™ is not our recommended supplement for raising depleted calcium levels - it is better suited to regular dosing to maintain proper calcium levels and boost coral growth. If you're having trouble maintaining your calcium level despite regular use of Reef Calcium™, it's likely that one or several other water parameters are out of balance.  The most common culprits are magnesium and alkalinity, but factors like low salinity can also contribute to a stubbornly low calcium reading.

1. Dose an ionic calcium. This is our preferred supplement type to boost depleted calcium.  Reef Advantage Calcium™, Reef Complete®, and Reef Fusion 1™ are all ionic calcium supplements.
2. Check your alkalinity. This is a measure of how resistant your pH is to change, and will go up when you add buffers like Reef Buffer™ to the system.  An alkalinity that is much too high will tend to precipitate calcium out of the water, leading to a depleted calcium level.
3. Correct ionic imbalances. Magnesium levels play a surprisingly important role in maintaining ideal calcium levels.  If you calcium levels stubbornly refuse to rise, it may be due to a magnesium level which is too low.  For high-calcium reef tanks, Seachem® recommends a magnesium level of 1300 mg/L or more.
4. Use a high-quality salt at the proper salinity. Natural seawater has a specific gravity of 1.025.  While it is possible to maintain corals or reefs at a lower specific gravity (down to 1.023), maintaining a specific gravity lower than this will tend to lead to issues maintaining proper pH, alkalinity, and calcium levels. 
5. Check your test kit. With surprising regularity, apparent difficulty changing water parameters can be tracked back to a faulty or inaccurate test kit.  Any time that you have readings that do not make sense given your dosing or the condition of your fish and corals, it will be worthwhile to double-check that your test kit is giving correct readings.  The Seachem® test kits have reference samples that can be used for this purpose, but with most other test kits it will be necessary to double-check your results using a separate test kit.