I opened my pool this year to find a massive scale problem, but I did two no-drain acid washes and the surfaces have pretty much returned to normal. I had the water checked at the pool store (I also did it myself but got some funny numbers) and here are the results (followed by the Pool School numbers for SWG pools)
FC 3 (poolschool = 3)
pH 7.4 (poolschool = 7.5-7.8)
TA 175 (poolschool=60-80)
CH 225 (poolschool = 250-350)
CYA 40 (poolschool = 70-80)
The obvious outliers are TA which is about 100 points higher than it should be, CH which is 25-100 points low and CYA which is about half of what it should be.
Since the test was done, I've added some CYA that I had from last year to bring it up, so that number should be back in the proper zone pretty soon.
My questions are, what should I do about the high TA and the low CH?
Another question is about adding "scale inhibitor". The pool store guy recommneded adding 8oz every few weeks, but I'm wondering if that's really necessary since there is no more scale and I'm keeping the ph low.