Hello,
A little background first - we purchased the home in April 2016; the pool was only 1 yr old (installed Summer 2015). It had a high (100+) CYA level. It took a full year to get the CYA level below 80. Most recently, the local pool store has reported our CYA readings as low as 30 (late June/early July) and as high as 60 (as of 7/27). As of 7/27, all other readings (ph, TA, Calcium, TDS, phosphates) are in normal ranges except free and total chlorine which are both 0; PH 7.4, TA 80, Calcium hardness 290, TDS 800 and 0 phosphates. We did leave the pool open over the winter months and for the most part only ran the filter when it was below freezing. the walls of the fiberglass did turn green but the water never did. in the spring, i shocked it, scrubbed the walls, and we haven't been able to maintain a chlorine level since yet the water is crystal clear.
We have an inline chlorinator that holds 3 inch chlorine tabs that I keep full and maxed out at a 5 on the "rate" dial. additionally, we use non-CYA powdered shock which will provide a chlorine level (not much over 3-5 and sometimes less) for about 8-12 hours and then fades away, by the following day there is 0 chlorine left in our water.
As of 7/27 (when i learned the CYA was back at 60), i have turned the chlorinator back down to a 3 only because nothing seems to help and now our CYA has risen! And, i certainly don't want to battle high CYA levels again! After a few days of not shocking the pool (because it's very expensive), i will notice some green discoloration (patchy areas) on the fiberglass walls. The areas aren't bigger than 2-5 inches and they scrub away easily with no residual effect on the water, i.e. the water does not turn cloudy at the area where i scrubbed the green discoloration. the local pool store tells me it's probably pollen rather than algae but they have no explanation or guidance (other than continual shock which is expensive) on the reason for 0 chlorine levels.
i'm getting really frustrated because i'm told fiberglass pools are the easiest to maintain! So far, it's been quite difficult!
i noticed an old forum (2010?) of a gentleman with a much larger capacity pool have the same issue and it was suggested to use bleach (household type bleach?) instead because there was most likely an algae still lurking. i used pool math to determine the amount of 6% bleach but not sure how many treatments i need to do to be sure this issue goes away permanently.
also - which is probably a side note and not related - our gauge reads around 40 since we've owned the pool. i noticed in another area of your site that the gauge shouldn't be much above 20? when the pump is off, the reading is 30 so i'm guessing we have a bad gauge?
i also have an automated vacuum that i run faithfully at the first sign of any debris on the floor of the pool.
my pool appears clean; people tell me they've never seen such a clean, clear pool but it's not sanitizing which concerns me greatly!
hopefully, i've provided enough information that some guidance can be given as to what i need to do next to rid myself of this problem, hopefully permanently.
thanks for any help!
A little background first - we purchased the home in April 2016; the pool was only 1 yr old (installed Summer 2015). It had a high (100+) CYA level. It took a full year to get the CYA level below 80. Most recently, the local pool store has reported our CYA readings as low as 30 (late June/early July) and as high as 60 (as of 7/27). As of 7/27, all other readings (ph, TA, Calcium, TDS, phosphates) are in normal ranges except free and total chlorine which are both 0; PH 7.4, TA 80, Calcium hardness 290, TDS 800 and 0 phosphates. We did leave the pool open over the winter months and for the most part only ran the filter when it was below freezing. the walls of the fiberglass did turn green but the water never did. in the spring, i shocked it, scrubbed the walls, and we haven't been able to maintain a chlorine level since yet the water is crystal clear.
We have an inline chlorinator that holds 3 inch chlorine tabs that I keep full and maxed out at a 5 on the "rate" dial. additionally, we use non-CYA powdered shock which will provide a chlorine level (not much over 3-5 and sometimes less) for about 8-12 hours and then fades away, by the following day there is 0 chlorine left in our water.
As of 7/27 (when i learned the CYA was back at 60), i have turned the chlorinator back down to a 3 only because nothing seems to help and now our CYA has risen! And, i certainly don't want to battle high CYA levels again! After a few days of not shocking the pool (because it's very expensive), i will notice some green discoloration (patchy areas) on the fiberglass walls. The areas aren't bigger than 2-5 inches and they scrub away easily with no residual effect on the water, i.e. the water does not turn cloudy at the area where i scrubbed the green discoloration. the local pool store tells me it's probably pollen rather than algae but they have no explanation or guidance (other than continual shock which is expensive) on the reason for 0 chlorine levels.
i'm getting really frustrated because i'm told fiberglass pools are the easiest to maintain! So far, it's been quite difficult!
i noticed an old forum (2010?) of a gentleman with a much larger capacity pool have the same issue and it was suggested to use bleach (household type bleach?) instead because there was most likely an algae still lurking. i used pool math to determine the amount of 6% bleach but not sure how many treatments i need to do to be sure this issue goes away permanently.
also - which is probably a side note and not related - our gauge reads around 40 since we've owned the pool. i noticed in another area of your site that the gauge shouldn't be much above 20? when the pump is off, the reading is 30 so i'm guessing we have a bad gauge?
i also have an automated vacuum that i run faithfully at the first sign of any debris on the floor of the pool.
my pool appears clean; people tell me they've never seen such a clean, clear pool but it's not sanitizing which concerns me greatly!
hopefully, i've provided enough information that some guidance can be given as to what i need to do next to rid myself of this problem, hopefully permanently.
thanks for any help!
