High CYA level - 120 - Drain half of the pool?

[DrNAB]

My pool has a CYA level of 120. I was using Dichlor and Trichlor for years but recently switched to bleach. Should I drain half of the pool and then refill it?

Also, the hardness of the pool is 310. Will I need to add calcium after I refill it? If so, should I just use calcium hypochlorite shock as my chlorine source until the hardness returns to normal?

 

[frustratedpoolmom]

If the CYA result is from a test strip, I'd have it confirmed with a drop based test, even if it's the 6-way from wal-mart, which is more accurate than test strips.

I wouldn't drain unless I had an accurate CYA reading from a drop-based kit.

If you do drain, yes, you can use cal-hypo to chlorinate and raise the calcium level into range.