Added CYA and pH took a dive...

[mariner09]

I'm practicing my POP with this, but thought I would throw this out for nibbles.

I just completed the conversion and am following BBB practices. I had FC at 8 and pH was 7.2. I added almost 4lbs of CYA to try to get to 30 and my pH dropped to 7.0 or lower. I added a 4lb box of Borax about 7 hours ago and no movement on the pH. Just put in another 4lb box of Borax.

The CYA doesn't seem to be measuring very well yet, but maybe it takes some time to get proper levels. Alk was up around 140 this morning.

Does pH usually start dipping when adding the proper chemicals to get things going?

[waterbear]

Cyanuric acid often will cause a pH drop when you add it. As long as your pH doesn't drop below 7.0 I would not worry too much about it. Where is your TA? A full set of test results would be helpful.

Edit: by full set of test results I mean Free Chlorine, Total Chlorine, pH, Total Alkalinity, Calcium Hardness, and CYA done with a drop kit or dry reagents and not strips.

[mariner09]

Can do, a couple of questions about that...

I use a Taylor K-2005 and when I do the TA test, I have a green sample and it tells me to add drops until it changes to red. Does the reading happen when it stops being green or when it becomes a true red? I think it's purple before it's red.

For CYA, the kit suggests to add the water + reagent combo until a black dot starts to disappear. Does that mean when it turns grey or cloudy or when it's gone?

Maybe I need to ask Taylor...

FC = 2.5
TC = 3
pH = 7.2
TA = 160
CH = 140
CYA = below 30

PS...Just reading one of Carl's posts tells me my CYA must be around 20 because the TA was 140 yesterday and it's 160 this morning...