Water tests are bouncing around - please help

jayden

Member
Jan 24, 2021
17
MA
Pool Size
12000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
My water was perfectly balanced until a couple of weeks ago when it first started showing slightly elevated CC. My CYA was at 50 since I had opened my pool, and registered as such on every test. I just tested at the pool store again yesterday and it showed my CYA at 4 - and they told me to add in another 4lbs of stabilizer, as well as shocking to remove the chloramines. I went back to the pool store and questioned the test based on my understanding that CYA doesn't leave the water, so I shouldn't have to add more. They tested again and this time it showed CYA at 50. They proceeded to go with a 3rd test which then showed CYA at 19 and that I now needed to add 12lbs of Alkalinity increaser - neither of the first 2 tests showed a low Alkalinity. All 3 tests showed FC and TC around 2.5-3 and showed ph around 7.5-7.8.

They said the chloramines are throwing the test off and that I should add in a gallon of shock tonight (seems like a lot for a 12k gal pool) and that I should still add in the 4lbs of stabilizer. I have no problems adding in the shock tonight, however is there ever a need to add in that much stabilizer? I only added in 4lbs of stabilizer to open my brand new pool to get it up to the 50 level. So the test is basically saying I lost all stabilizer. I do not backwash, and there has been no draining of the pool. Just typical splash out water use and topping off with the hose. This is a brand new fiberglass pool (all new equipment) but has been opened for a few months and all the levels were maintained perfectly until the last test a few weeks back that started to show elevated CC. Also my pool water is crystal clear. Typical water temp is about 85.

Any thoughts?
 
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Yeah.. I got lots of thoughts. the first one is don't go back to the pool store and do your own testing! You have just experienced how inconsistent they are.. and how they recommend different treatments based on whatever came out that time. Its maddening.

So read this:
Test Kits Compared
and since you have a SWG get one of these:

Don't add anything to your water except 5ppm of liquid chlorine until you can post your own results.. and then we will take it from there.!
 
This is very common unfortunatly and a source of much confusion for pool owners. Relying on free testing will end up costing you plenty with no stress relief. Investing in a proper kit is the first step in getting your pool on track. Take charge.
 
Thanks - I appreciate the recommendations on getting my own test kit. I will definitely go that route. Before today everything was in-line with their testing so there was no reason to question it.

@mguzzy - I have not been shocking regularly, and I do not add chlorine - the SWG has been keeping it between 2-4ppm for 2 months now w/out issues. The CC was at 0 until 2-3 weeks ago. The only deviation of anything out of normal range before yesterday was the CC. They told me that to keep the CCs down that I should be shocking weekly, which I do not. I took the advice of what I read on this forum that you don't need to shock regularly and let the SWG do it's thing, which I have been doing. However now with all these levels bouncing around and with elevated CCs - I will probably shock and retest in a few days.

I will shock and re-test. They told me to shock AND add stabilizer which to me didn't make sense. I was looking for confirmation that there's no way CYA could bottom out in a month so I should just shock and not add the CYA.
 
“Shocking” means different things to different people. We don’t shock TFP pools the way pool stores recommend, once a week or whatever. If you maintain your FC levels per the FC/CYA chart referred to above you won’t get algae. The only way to do that is with one of the test kits referred to above. Don’t add anything to the pool until you have test results from your own kit because we don’t know which test results to believe. Any additions could make things worse.
Most likely the 2-4ppm was too low for your cya, allowing algae to get a start, but that is only a guess.
Order a test kit, while waiting read through pool school and peruse the many threads of questions and answered by the experts while waiting. Welcome to TFP !
 
This is how I do my SWG pool.. I keep my CYA at around 70ppm... that seems to be the sweet spot for my pool. Besides the recommendation for a SWG pool is on the FC/CYA Levels. And I target my FC at 9-10ppm. If you are keeping yours at 2-3 that is too low to accommodate any unplanned FC demand. Your pool will easily use 3-5ppm during the peak of the summer. Throw in an unplanned pool party or a heat wave and your hosed. At 10-ish I can loose 5ppm and still be above the target level we suggest here. As you read more you find you can really keep your FC at any level below SLAM concentrations for your CYA and not have an issues.

Mind you this is the TFP methodology and pool stores use a methodology that is frankly out dated. So their advice is based on that, and won't match what we recommend. But you may have figured that our.. you are here! :cool:
 
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This is how I do my SWG pool.. I keep my CYA at around 70ppm... that seems to be the sweet spot for my pool. Besides the recommendation for a SWG pool is on the FC/CYA Levels. And I target my FC at 9-10ppm. If you are keeping yours at 2-3 that is too low to accommodate any unplanned FC demand. Your pool will easily use 3-5ppm during the peak of the summer. Throw in an unplanned pool party or a heat wave and your hosed. At 10-ish I can loose 5ppm and still be above the target level we suggest here. As you read more you find you can really keep your FC at any level below SLAM concentrations for your CYA and not have an issues.

Mind you this is the TFP methodology and pool stores use a methodology that is frankly out dated. So their advice is based on that, and won't match what we recommend. But you may have figured that our.. you are here! :cool:
For what it’s worth, before I fully committed to the TFP method, I had my CYA around 40 or 50, and FC about 4ppm.
I had issues with these levels as soon as the weather turned super hot. Since then (three or so weeks ago) I’ve been keeping CYA at 60 and now have it at 70 for the first time and running my pump a bit more to maintain FC around 9ppm, which is slightly higher than the CYA/FC chart but the thing I’ve noticed is that since I upped my CYA the FC hasn’t really drifted down much at all over the past couple of weeks. I’d def get the CYA up to the 70 mark and test it on your own. Those pool store results you shared are so wildly different for CYA something is clearly off there.
 
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