Balanced Pool, Still I have algae?

[Pkern]

I have a question - maybe you can assist? My pool is well balanced, but some algae is still growing on the walls - mostly the walls in the shady areas.
PH - 7.4
Chlorene - 3.5
CYA - 60
The algae brushes off very easily.
Thanks for your help!

 

[Griswald]

For CYA of 60, you should never go below 5.0 FC and should be closer to 7.0.

That's why you have algae.

 

[proavia]

How are you testing your pool water?
How old are your reagents?
Test Kits Compared

I see you have PoolMath linked to your forum account, but the last additions and tests are from 2 and 3 years ago.

See FC/CYA Levels for the target range for your CYA level.
Without algae you need to dose for the high side of target range.
With algae, you need to SLAM Process.

 

[Pkern]

Tf 100, but the chemicals in the kit are at least a year old, perhaps closer to two…

 

[Pkern]

I bumped my chlorine from 40% to 60%. Hopefully this will do - I can’t slam for a few days - busy at work! But I will double check the chemicals in the AM. Thank you!

 

[proavia]

Has your TF-100 been stored outside or inside in an air conditioned space?
While it is stated that the reagents are good for 1 year, you can usually get 2 years out of them if stored in a climate controlled area.

Don't forget to stock up on liquid chorine before you start the SLAM Process

 

[Pkern]

So here’s an update. Thank you all for your advice and help. I re-connected to the pool math site so I can track my chemical levels better, and I purchased a new set of chemicals for my TF-100 test kit. I have bumped my chemicals to the levels suggested here and no more algae - so I didn’t do the SLAM process. I am assuming that there is no reason to SLAM the pool if the algae is gone, correct? Thanks again all.

 

[proavia]

Great!
Still suggest you do an Overnight Chlorine Loss Test to be sure.