Newbie help needed

[Popster]

Hi,
I am new to the forum and I need some advice. We have had our pool since Sept 2020 and just enjoying it now here in SoCal. It is about 16000 gallons and material is mini pebble. I have been trying to maintain the pool by myself; so far the water is clear. I have been shocking the pool weekly from the bags of shock treatment I bought at Sam’s club (dichlor), putting 2 cups of Perfect weekly once a week, and maintaining it with a 3in chlorine tablet. I go to Leslie’s around once a month to have my water tested. The last test didn’t look great: the CYA is up to 147! After reading here I guess my course of action is to switch to liquid chlorine and do away with the chlorine tabs. I also have to drain at least half the water in my pool now and add fresh water, then go from there. I also ordered the TF-100 test kit which will hopefully be here next week.

Here are the rest of my pool chemistry results:

Ph 7.7
Alk 83
Cya 147
FAC 7.3
TAC 7.3
CH 222
TDS 900
Pho 115
Fe 0
CU .3
Thanks in advance for all your help!

 

[Oly]

Welcome. You are on the right track and obviously are able to find the wealth of good info on this site. Keep chlorine in your pool until you get your test kit then post your results. You will have lots of help from friendly pool owners here.

 

[Popster]

I have been reading in the forums but I cannot seem to find how much water I need to drain in my pool (16000gallons) to lower my cya levels to 40-50 range. Pool math didn’t give me the amount of water to drain either.

 

[Oly]

Don't take action assuming you know your actual CYA ppm. Wait for your test kit to arrive and confirm your chemistry before attempting to correct things you believe are wrong.

 

[Newdude]

Hey popster and Welcome !! We had a newb just over a week ago that the pool store claimed 115, which would need a 75% drain, and when her kit came she was a 30. Maybe your store was right that day. Maybe not. They are inconsistent at best and God awful at worst.

Anywho it's an even percentage or fraction to figure out how much to drain. A 50 % drain would lower you by half, 2/3 by 2/3, etc. There is no CYA in any fill water so the fresh stuff is 0.

*if* your CYA is really a 147, a 73% drain would get you down to a more manageable 40.

 

[Popster]

Thanks for the help guys! I guess I’ll just wait for the test kit.

 

[Popster]

Got my TF-100 test kit, tested for the past 2 days, and the numbers are as follows:

Ph 7.5
FC 8
CC 0
Cya 80
Calcium 300
Alk 100

I diluted the CYA test and both days yielded similar results (40x2=80). I am now in the process of draining 50% of my pool. I will then replace the water afterwards tomorrow morning then test again from there, then balance as necessary. Are there any other points that I missed? Again, thank you guys for your input!

 

[Newdude]

I diluted the CYA test and both days yielded similar results (40x2=80

Nice extra step to verify accurate results !!
(Also much better for you it’s not 147 like *somebody* said). Well done.

the fill water will change the other results so see what happens once it’s filled/mixed and we can go from there.