Well I just joined, so i'd like to volunteer a tip that has probably saved me a couple of thousand dollars over the years i've been reefing. I have a swimming pool, which as it happens, requires both calcium and alkalinity in very large quantities. One day, after buying $100 worth of B-Ionic, I decided to try mixing a couple of cups of each with r/o water and mix it in the gallon jugs I got from B-Ionic. I've been using it ever since (about four years) and I have had no problem I can attribute to these chemicals. My coral growth has been excellent. I don't have much crystalline algae, but that's probably because I keep the Alk at around 8 or 9 instead of 10-12.
Calcium Chloride and Soda Ash can be purchased locally at any pool store, but I get mine at Leslie's because its cheaper. If you're looking for ways to save some bucks, you might want to consider it. Eric