Tips for Testing Calcium
Calcium testing in marine systems is
fraught with difficulties. Test kits generally donít work well in the
ranges run in reefs, and many ions in marine water interfere
with the kit. If your calcium level does not make sense, try diluting the
aquarium water sample 50/50 with distilled, deionized or R/O water and
testing. Multiply the result by 2. This will both save on valuable
reagents in your kit and generally give a more accurate reading.
(You may want to consult with the kit manufacturer to determine that doing
this will give valid results with your brand of kit).
If you have trouble maintaining calcium or buffer level,
check to see that your salt mix
has adequate magnesium.
To save money and increase dissolvability, some
manufacturers of popular newer salts have included only half the level
of magnesium necessary in their sea salt mixes, resulting in low
calcium solubility and poor buffering!