What's raising my cya so drastically?

[PoolMeasuringContest]

Long time viewer but this is my first post. I've got 26000 gallon peanut shaped pool that I WAS using 2 trichlor pucks in plus 2 bags of pool store cal hypo weekly. (Leslie's power powder). But let's go back. When I started opening my pool two months ago my cya was literally zero. So I did what I do when it's zero and I added small amounts at a time over the course of a week or so til it was between 20-40 per 7 way test kit. Well, started with normal yearly regimen 2 bags cal hypo granules, about a liter of muriatic acid and two floating pucks. When I was at the pool store every word out of their mouth was phosphree and buy this then drain the pool and get some more phosphree. So I called somewhere else and he said switch to a non chlorine shock every other week and get rid of the pucks altogether. He also told me because of where my pool is (direct sunlight in a desert literally surrounded by cow farms) it's been better for his customers to have a cya near 80 to combat the rapid breakdown of chlorine from the intense sun and rapid floral growth from all the farms. My pool is still clearer than tap water but I can't figure out why my cya is going up. These are my pool test results from yesterday pre-chlorine treatment.
FAC-1PPM
TAC-1.5
CH-180
CYA-100
TA-120
PH-7.8
Copper-0
Iron-0
TDS-600
Pho-100

 

[jblizzle]

Welcome to TFP!!!

Were you adding granular CYA? How much did you add in total? That often takes up to a week to show up on the test, so it sounds like you may have been testing too soon and added too much.

Did you do all the CYA testing? What you posted smells of pool store numbers. Which kit do you have?

You should not need to be up around 80ppm ... 50ppm would be fine.

 

[Richard320]

Welcome to troublefreepool It's about time you stopped lurking!

Yeah, those results look like pool store tests. Pool store test results are generally suspect, and the CYA test most of all.

 

[BoDarville]

When doing the CYA test, lighting is crucial. After mixing the CYA reagent with sample pool water, stand outdoors (ideally at late morning-early afternoon on a bright sunny day) with your back to the sun and hold the view tube at about waist level. Looking down into the view tube, slowly pour the mixture from the mixing bottle into the view tube until the black dot is no longer visible.

Last year, I ran an experiment where I did the test as describe above and then immediately took a sample to the pool store (about a mile away) just for grins. The CYA result I got by self-testing was 40 ppm; The pool store got 80 ppm. Of course, they tested inside where the lighting was not as bright as performing the test outside.