I've had trouble lately keeping a decent reading of FC. After shocking with either trichlor shock powder or bleach, it goes down rapidly. I usually keep at least 3-3in. trichlor tablets in the floater as well. It's also difficult to raise pH above 7.1 or so, even when adding 2 - 3 times the recommended amount for the pool size. The latest test results from local pool store show VERY high readings in some areas, to the point that I suspect they may not be accurate.
TA 240 (!)
CH 600 (very hard water in my area)
CYA 250 (!)
With numbers like these, should I just do a couple of half-drains and fills to bring numbers to more reasonable levels instead of pumping in more chemicals to try to make the adjustments? Thanks for any info or insight...