What salt do you use?

[rickjames]

Originally Posted by Matt

From my reading, IO, Reef Crystals, and Kent salts are all made by the same manufacturer (Aquarium Systems), and apparently test very similarly.

Not entirely true. IO is formulated to mix with an "average" amount of minerals in water (i.e. tap water). Kent and others are formulated to mix with RO/DI water.

If you mix IO with RO/DI water you end up with about 330 ppm calcium, depending on the specific gravity of the water, and a lower alkalinity.