New pool owner...test results

[Zachawny]

Our pool was started 4th of July week and has been finished about two weeks. We got delayed because of all the rain we had in July. Here is a pic of the finished product, the kids are having a blast.

Here are my first set of test results since I received my TF-100.

Salt: 4200 (test kit) 3900 (Hayward Aqua Plus)
FC: 8
CC: 0
TA: 90
CH: 190
CYA: 20
pH: 7.8

The pool is approximately 18' by 36', 3.5' shallow to 8.5 deep, and approximately 23,000 gallons. Pool is vinyl liner. Equipment is Hayward Aqua Plus, T-15 salt cell, sand filter, and Hayward Super Pump VS.

I know the CYA is low and the FC seems high. SWG is currently set at 50%. I run the pump at high speed (3000 rpm) for 3 hours per day and low speed (1500 rpm) the other 21 hours.

Any relevant help is appreciated. Thanks.

 

[DorsalSpine]

Our pool was started 4th of July week and has been finished about two weeks. We got delayed because of all the rain we had in July. Here is a pic of the finished product, the kids are having a blast.

Here are my first set of test results since I received my TF-100.

Salt: 4200 (test kit) 3900 (Hayward Aqua Plus)
FC: 8
CC: 0
TA: 90
CH: 190
CYA: 20
pH: 7.8

The pool is approximately 18' by 36', 3.5' shallow to 8.5 deep, and approximately 23,000 gallons. Pool is vinyl liner. Equipment is Hayward Aqua Plus, T-15 salt cell, sand filter, and Hayward Super Pump VS.

I know the CYA is low and the FC seems high. SWG is currently set at 50%. I run the pump at high speed (3000 rpm) for 3 hours per day and low speed (1500 rpm) the other 21 hours.

Any relevant help is appreciated. Thanks.

The FC is high and your CYA is low for a SWG. I'm not sure about the PH for a SWG since I don't have one. I'd read the Pool School section on owning a SWG and go from there. You seem to have a good handle on things.

 

[Zachawny]

I forgot to mention that I added 6 lbs of stabilizer this past weekend per the pool builders instruction. They were getting a test result of zero prior to adding the stabilizer. I know it takes a little while for the CYA to show up on the test.

 

[DorsalSpine]

I forgot to mention that I added 6 lbs of stabilizer this past weekend per the pool builders instruction. They were getting a test result of zero prior to adding the stabilizer. I know it takes a little while for the CYA to show up on the test.

The pool calculator will give you an idea of how much to add. It's usually a good idea to add it over time or keep really good track of how much you add. It is easy to add and difficult to remove. Dumping water to lower CYA is something I know a lot about. One of the few things I'm an expert at.

 

[BoDarville]

I forgot to mention that I added 6 lbs of stabilizer this past weekend per the pool builders instruction. They were getting a test result of zero prior to adding the stabilizer. I know it takes a little while for the CYA to show up on the test.

Starting from a CYA of 0, the 6 lbs of (presumably) granular stabilizer will get your 23,000 gallon pool to 31 ppm, per the Pool Calculator. And, yes, it does take about a week for all the CYA that was added to show up on a test. With a SWG, you want to get the CYA up to around 70 which means you will need to add another 120 oz of granular stabilizer. DorsalSpine has a good point that CYA is much easier to add than it is to remove if it gets too high, so if you wanted to add a little less than 120 oz to be conservative, that would be fine. After dosing, remember to wait a week to test the CYA level.

Your FC of 8 ppm is a little high. You can bring that down slightly as the target SWG FC for a CYA of 70 is 5 ppm.

I would also keep an eye on pH. It's fine now at 7.8, but it is at the upper limit of what we recommend. However, note that the CYA additions should bring pH down, although some of that drop could be mitigated by the aerating effect of the fountains. Again, the answer is testing pH several times a week.