Re: Caltreat for lowering calcium hardness in pools
Draining and refilling may -- or may not -- help. You need to test your FILL water, to find out. Some water systems supply water that is quite high in calcium.
I'm not sure what's in Caltreat and I've never trusted United Chemical's products enough to test them on my customer's pools. The reports I've seen on results have been very spotty, ranging from "made things worse" to "worked, but took much more product than the literature suggested".
Lime softening -- explained here [ http://www.poolforum.com/pf2/showthread.php?16992 ] -- does work, but requires careful attention to detail. If you are willing to follow the process, it's fully explained in that thread. Just be aware it will take awhile to clean all the particles out of the pool and water.
If your filter is in poor condition, I would repairing it, first.