I tried that 2-part mixture... after the first night of over guessing the concentrations needed and OD'd the tank a bit. But once I got things settled out and diluted the calcium side of it to suit my needs (Oceanic salt mix is already quite high in calcium content) it worked quite well. Easily able to keep calcium over 480ppm and Alk around 10dKH.

But for cheap!

What did your calculations work out to for making up the 2part mixtures?

Baking soda I found at WallyWorld in a 5 pound box for like $4 or so.
Even managed to find a place to order in actual Dowflake for me, ordered three 50# bags, two ended up spoken for before I could even pick them up but still have 2/3 of a bag.

Pretty sure Jason has been using Type-S something available from HD in large quantities for cheap too. Not available around us for some reason.