Another drain pool thread...


Jan 26, 2020
Palm Beach Gardens, FL
Since taking over the maintenance of my pool I have been struggling to keep the algae away. I have been through the SLAM process successfully twice now as a result of yellow algae. I have been diligently brushing and vacuuming the pool and cleaning the filter.

As per the Chlorine / CYA chart I have been keeping chlorine levels within the ranges listed for my cya levels. When I started all this back in February cya was around 60 and has gradually come down to 25 where it is now as I have been using liquid chlorine vs. the pucks which were being used before.

If I let the chlorine levels drop anywhere near the lower end of the range the algae returns. I am seeing algae again as we speak. :(

Current Readings

FC 5.0
CC 0.0
PH 7.8
TA 75
CH 300
CYA 25

I know TDS doesn't mean much but they are over 3000. I have had the pool for 5 years and the previous home owners did very little in the way of maintenance on the house let alone the pool so I'm assuming it has not been drained in 10+ years.

Is it time to drain it or partially drain it? My challenge is that it has been raining a lot and will likely continue to rain for the coming weeks so a full drain is not an option. What about draining water from the top of the pool with a pump and garden hose while filling at the same time using city water and a hose positioned at the bottom of the pool. i.e. cold clean water stays low and dirty warm water stays high. Let it run like that for a day?


Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
Laughlin, NV
So the TDS that matters you show as CH of 300 and CYA of 25. Those are fine, except the CYA is a bit low.
The other component will be salt (have you tested that?) and phosphates. Phosphates typically are of no consequence. If you would like to test for them, Taylor makes a test kit. Taylor k-1106.


Jan 26, 2020
Palm Beach Gardens, FL
I will pick up the kit mentioned. Do I need another kit to test for salt? If phosphates are of no consequence are there any other kits I should be picking up to test for things that might be of consequence in this situation or others that arise in the future?

Just before I parted ways with the pool store they had me test for nitrates with a test strip and the readings were 40+ if I remember correctly.