Every year, end of July-early August I get an algae bloom
This year is no exception.
I have an AquaRite a SWG system and this year maintained Cl above 5.
Pump ran 12hrs /day.
Last week pool started turning slightly. I increased the pump to run 24/7, and added clarifier.
I vacummed up the next day, then went on vacation for a 4 days.
Upon return, I have large deposits of green/yellow looking algae.
When I turn the SWG off at night, I do not drop Cl
My measurements are below:
CH (not measured)
Salt=3800 (Test Strip)
Salt=3200 (AquaRite Meter)
I ran out of CYA reagant, so I went to the Pool Store where I buy my liquid Chlorine, and asked them to measure it.
I did not believe their CYA measurement, as I had monitored this earlier this year.
So I bought some Taylor CYA reagants at the store. When I came home I measured CYA as 50.
So I went back and asked the PS to remeasure using their system (I think it was called True View 2).
I then had them measure the same sample with the Taylor reagants they just sold me.
They confirmed the discrepancy, but without any explanation.
So I went to another PS.
The rest of the measurements were reasonably similiar.
Q1 Why do I have a cloudy pool, if my Cl hasn't dropped below 5, my CC=0, and my FC doesn't drop overnight?
Q2Can anyone explain
a) CYA ranging between 40 and 100. (250%)
b) Salt range from 2900 to 3800. (30% error)
I know everyone on the forum recommends to trust your measurements, but how can this variation be possible.
Since I'm having this problem annually, I recognize I must be missing something. CYA measurement error seemed like a probable cause.
Here is my plan to treat the pool.
a) Shock pool to Cl=29 (assuming mustard algae and CYA of 50)
I don't have an FAS/DPD, so I will calculate from the pool volume, and I'll measure using the dilution factor of 10:1, which makes it just a bit better than meaningless
b) Vaccuum pool
c) Add algaecide Polyquat 60, vacuum again.
d) Once cleared, I'm going to try some filter cleaner that I was sold, but I remember some discussion about it on this forum.
PS recommended I use alaecide instead of shock, but I decided against it. (Algacide instructions indicate this could be done)
Any other recommendations or comments would be helpful