I buy all of mine from from local people from a reefclub. Usually it is a lot cheaper. One of my first was a large rock full of GSP. Now it is all over the back wall ha, I think it looks pretty cool. As far as dosing goes I would use the kits off of this website http://www.bulkreefsupply.com/store/products/calcium-alkalinity-magnesium
I have one of the kits, all you gotta do is refill it every once in awhile, its super easy. Just squirt a little in your sump every day or so...
I have one of the kits, all you gotta do is refill it every once in awhile, its super easy. Just squirt a little in your sump every day or so...