In a marine aquarium strontium plays an important role in accelerating the growth of coral and calcareous algae and natural sea water contains approx. 7 – 9 mg/L strontium.
Strontium is very difficult to test for, but if there is found to be a depletion of calcium in the aquarium then strontium levels are likely to be very low as well. It is advisable to maintain a strontium concentration of between 5 and 20 mg/L.
Salifert was the first to introduce a strontium test kit and this test measures both ionically free and moderately complex strontium in increments of 5 mg/L. Sufficient for up to 40 tests. For marine use only.