I used to live where water was liquid rock and goldies were happy. New location and just getting back into hobby after a few years off. Tap water is gh and kh ~50ppm. The fish I have are a bit off and I suspect this is why. I'm running a 40 gal now, but am resealing a 210gal and breaking ground on a 1,000 gal stock tank pond. Breeding is something I'm interested in as well in the next couple years. So, this is going to require massive amounts of water changes with additives for kh and gh. Kh is baking soda. What do you guys use in bulk that is budget friendly and quick dissolving for gh? And how do you add it for water changes on such a large scale?