Some chemistry off - recommendations?

[Chellayh]

FC -over 5.0 ( don't have the FAS-DPD yet - I know I need to get it.)
pH - 7.8
TA - 100
CH - 250
CYA - over 100
Salt - 4500 ( per Leslie's)

New fiberglass SWG pool. I added 10 bags of salt when we opened 3-4 weeks ago. SWG was happy until I added hardness increaser, then it started flashing high salt. i guess it is reading the CaCl as salt too, since it is technically a salt. It doesn't give me a number, just flashing lights to indicate low or high.

Not sure how CYA got so high, I added less than the pool calculator recommended. (But I have had that happen with pH adjustments too, so I have gotten where I add only 1/2 to 2/3 what it says then retest. ) The black dot disappeared about 2/3 the way to 100.

I wanted to get a number on my salt, so I took the water to Leslie's. They said my salt was 4500 & my CYA was 50. Not surprised on their CYA reading - few weeks ago they told me it was 60 when none had been added yet. The same guy was the one who did the test today - last time he told me that 60 was "practically nothing".

I added 18 oz MA tonight after the test to bring the pH down some. Not sure whether I should mess with the other stuff or just leave it alone since the pool is looking great.

 

[UnderWaterVanya]

Change some water out to reduce cya and salt.

-sent with Tapatalk 2

 

[257WbyMag]

If your CYA was 100, then the black dot would have been gone pretty much immediately upon adding drops to the view tube rather than 2/3 the way to 100. I think you may be reading your CYA test wrong.

Why did you add hardness increaser? Low CH is not an issue with fiberglass pools, although a high CH would be.

 

[chem geek]

Was the 2/3rds on the way filling up to the 100 ppm line as shown in the scale here?

If so, then that's > 100 ppm CYA. Remember that the scale is reversed so starts out high and then gets lower as you add more to the tube.

 

[Chellayh]

@ chemgeek: Although I have a separate cya tube, yes, the scale is like that shown in your pic. The water level had not reached the mark for 100, was 2/3 up to it.

@ 257Wby Mag: Pool School recommends a CH level of 220-320 for fiberglass pools. Mine was 60 before adding calcium. I read many of the forums r/t hardness level before adding it, but never saw anything that said the swag would read the increased as salt. If so I wouldn't have added all 10 bags before adding the CaCl.

I was afraid you all would recommend a partial water change, just hoping I really wouldn't't have to!

 

[UnderWaterVanya]

Check your CYA again with 50/50 tap water and pool water then double the result. This will help you figure out how much water needs to be ditched to get back to rational CYA - the salt is another factor that can help you figure out how much minimum you need to change.

Are you planning to winterize? If so maybe you can do the bare minimum to get salt down a little and then wait until next spring to resolve the cya issues.

 

[Chellayh]

Thanks. I knew I had read a way to get a better reading on the cya, just couldn't remember.

Haven't decided whether we will winterize or not. In any case we want to keep it open until end of Oct, so it would probably be better to take care of it now.

 

[UnderWaterVanya]

Thanks. I knew I had read a way to get a better reading on the cya, just couldn't remember.

Haven't decided whether we will winterize or not. In any case we want to keep it open until end of Oct, so it would probably be better to take care of it now.

If you don't have algae - you can make it work with the current CYA until October just fine. The salt you need to fix if your SWG is complaining.