Here we go (green) again.


Active member
May 19, 2018
Brantford, ON, Canada
I thought I was doing really well this year but, I'm now in the beginning stage of a bloom.

I've been keeping my chlorine between 2 & 4. The problem is that I have no way of measuring CYA right now. My reagent is gone and I can't get another set because I can't enter the U.S. because the borders are closed.

When Covid first hit (March) I went to Walmart and bought 2 buckets of hth pucks and a 6-pack of hth shock because I didn't know if our pool stores were going to be open or not. I've been using 3 pucks per week to keep the vale from 2-4.

A few days ago the water seemed to be losing its sparkle. I went underwater and it wasn't cloudy but it wasn't clear either. I decided to shock it so I put 30g of shock in (in addition to the pucks that were in there). The next day I notice the chlorine wasn't any higher so I put 150g in. The next day it was starting to turn green. Not quite green yet, but kind of a cloudy aqua-ish colour. Then today the same thing but now I can see swirls of yellow algae on the bottom.

Today I discovered I accidentally went too low with the measurements. Based on the size of my pool, I should have put 4x the amount of shock in.

I added 2 cups of liquid chlorine today.

I have used my TF-100 KIT and gotten the following results:

FC 13 (after adding 2 cups of liquid chlorine today)
CC is 0 or maybe 0.5 it was pretty tough to tell
TA 60
PH 7.5
Calcium 150 maybe 200 (it kind of looked a little purple at 150 and blue at 200)

I took the water to a pool store today and they tested it. I wanted to see if CYA was really high. They gave me the following readings.

FC 11.9
TC 11.9
CC 0
PH 7.9
ALk 75
CYA 76

They said not to worry about copper because their machine was reading high for some reason.

Which readings should I go by?
Should I worry about their reading of 7.9 on the PH or should I go with my 7.5 with the tf 100 kit?

There are no CC's.

Does anyone know how much CYA is in the hth pucks?