On Wed, 7 Aug 2013 00:19:20 -0700 (PDT), Mitch Harmatz
wrote in rec.aquaria.freshwater.misc:

Along with calcium carbonate several other important minerals and minor elements are present in milk, butter milk, all types of milk products. Non-dairy products can be listed as ready to cereals, cocoa puffs, beverages, fruit juices, etc. Calcium is mostly present in the form of calcium carbonate in various food substances.

I doubt that any person will put milk, butter milk, or any other type of
milk products into their aquarium.
But you are very welcome to tell us how to _REMOVE_ unwanted calcium
carbonate from our aquarium water.

Thanks

jue