Low Alkalinity and Algae

[Zlynch]

Just as a general question, if a pool has an algae breakout and their test shows a low alkalinity level should they raise the alkalinity first? Or try to clear up the pool first with shock and algaecide?

I have gotten mixed answers on this over the years, and I'd love to train my staff the right way.

Thanks!

 

[zea3]

Hi, welcome to TFP! TA will fluctuate as you fight the algae. Get rid of the algae first, then balance the other chemical values. The only exceptions are lowering pH if it is above 7.8 and lowering CYA if it is above 30. Keep in mind our CYA recommendations are for homeowners caring for their own pools and that commercial pool regulations vary by location. Our recommendations are designed for homeowners and may not be practical for pool service companies, but I do believe the basic chemistry guidelines we use and the science behind our recommendations will have value to your business if you choose to incorporate them.
As for treating algae, I would not recommend algaecide. It is a mild preventative at best and does nothing to kill existing algae outbreaks. High doses of liquid chlorine is the most effective treatment we recommend.
We have several articles on our website that explain the TFP method of pool care you may find useful.
SLAM Process,
FC/CYA Levels
Pool Care Basics
Please feel free to ask any questions you may have.

 

[Newdude]

How low is low ? How are you testing ? The adjusted Alkalinity at the pool store often reports low when it's not. Then they sell you really spendy baking soda to jack the TA.

I would not recommend algaecide. It is a mild preventative at best and does nothing to kill existing algae outbreaks

Not only that, but chlorine consumes the algalecide and vice versa, leaving less of both. It's counter productive during the regular season.

 

[Zlynch]

Thank you both for your responses. Tests are done with a Waterlink spin lab, and with a 30-40 in TA. I know that chlorine consumes algaecide, but I had thought that you just wanted to space out a shock treatment and application of algaecide. I had not heard that standard sanitizer levels of chlorine will negate algaecide. Thank you for the information