[Canadian Man]

Originally Posted by EmilyB

I've never had anything but a hugely positive experience ordering from J&L.

Mee too.

You might be able to keep up the demands of calcium and alk in a reef tank with tap water, but it depends largley on the type of corals you keep.
Softies, fine calcium from tap water may suffice but many stonies and you have to add calcium/alk some how and more than tap water will add.
I use only a calcium reactor on my system and that's all the additives I use.