I have spent some time in Pool School (vinyl). I have an indoor IG 5200 GAL Endless pool (EP) that went online AUG 2012. The water has not been changed since 2012. I keep the pool at 87 degrees. I use bleach, sodium Bisulfate, and baking soda, however over last three years, I have probably shocked the pool 1 or 2 times a year with DY-CHLOR (Dura Shock). As embarrassing as it sounds, I have never measured the CYA until today since EP told me it was something I did not need to measure because the pool is indoors and obviously has no direct sunlight and it is covered when not in use.
Here are my numbers today using a new (one month old from the fractory) LaMotte ColorQ Pro-6 using Pool Math (PM):
Pool math (another software program: perfect pool software) both say I need to drain the pool and replace 36% of the water. PM also wants me to add 6 oz of CACL to increase the CH.
The water looks clear. I don't see any mustard algae.
1. Is it necessary to drain the pool? My CYA should be 20 to 30 for an indoor pool correct?
2. Do I need to increase my FC goals (currently 2-4) to 4 - 8 which PM is showing?
3. What is a good CSI range for my pool?
4. In the future, Can I simply use bleach to do a SLAM? EP confused me since they sent a package of Di-CHOR when I first purchased the pool, therefore I have been using Di-CHOR to Shock the pool.
5. Is the Di-CLOR the reason my CYA is so high?
6. I Have no experience with Mustard Algae. Does it happen many with outdoor pools?
Sorry for the long post. Even though I have been balancing this pool for three years, I have never acquired the knowledge that I have since joining this forum and reading Pool School.
Thanks so much in advance,