Green Pool Problem

[thejglady]

"Hello, I have no idea what is going on with my pool. Any help would be appreciated. Spending a fortune on my pool with no improvements.

I own a 26,000 Gal Pool with a large Haward DE Filter.

The pool has been perfectly clean for 3 years, but we have a new baby and ignored the pool, not needing to use it. In August I forgot to Chlorinate the pool for 3 weeks, lifted the cover and noticed the pool was turning green, and the pool cleaner was stuck not cleaning the pool. I first cleaned the filter in September and the pool was turning clear, then it went back to green in October. I dumped 2 liters of Algecide and about 6 galons of Liquid Chlorine in the pool two weeks ago, which turned the pool from Dark Green to very light green / very cloudy. I cleaned the filter quickly today (disassembled and hosed down filters) (the pool filters both times looked like they were covered in BRIGHT GREEN MUSH) and poured 5 cups of DE into the skimmer with the motor on. The Filter before cleaning was at 40 PSI, after cleaning was at @14 PSI. I poured 1 Gallon of Liquid Chlorine in the pool with about 12 oz of 20% Algecide in the pool and 1 qt of pool charifier. After 8 hours I noticed the pool filter pressure was back up to 34 PSI and pool still looked very cloudy with a light green hue color.

What is going on with my pool? I read about using detergents on the filters, is that what I should also be doing? Do I need to clean the filters several times to get all the particles out of the pool (is that normal)?

Any suggestions would be appreciated, i have all ready spent about $180 this month on chemicals with nothing to show for it."

Mod note:The above part is from an old thread. The below is a new reply to it.


this is really late in coming as a reply, and might even be an answer you already have seen, but it sounds like this pool has a chemical lock. The only way to solve it is to drain 2/3 of the water and refill. Then test and treat the water as necessary. Chemical locks are caused by the conditioner in a lot of chlorine products. After 3 years there is a lot of conditioner built up in the water. Hope this helps someone.

 

[kimkats]

Re: HIGH PRESSURE after cleaning DE FILTER - POOL CLOUDY GREEN

this is really late in coming as a reply, and might even be an answer you already have seen, but it sounds like this pool has a chemical lock. The only way to solve it is to drain 2/3 of the water and refill. Then test and treat the water as necessary. Chemical locks are caused by the conditioner in a lot of chlorine products. After 3 years there is a lot of conditioner built up in the water. Hope this helps someone.

There is no such thing as "chemical lock". Your CYA can become too high and cause the need for copious amounts of FC. You are correct in saying the way to fix the high CYA is to drain a portion of the pool. We would use Pool Math as seen at the top of the page to see exactly how much water to drain AFTER doing a test to see just how high the CYA was.

I hope you read this link:

Pool School - ABCs of Pool Water Chemistry

This will start you on the path to learning about how things are done here at TFP.

Kim

 

[Texas Splash]

Welcome to TFP! Kim's right about the chemical lock. Based on your elevated CYA and what you've added to the water (several algaecide treatments - adding copper) it's best to do a healthy water exchange. Please remember that no amount of filtration will kill algae. You may catch some of it, as evidence by the skyrocketing psi on your filter gauge, but the algae is still alive in your pool. Only the proper amount of chlorine (consistently) will terminate the algae. That's where the TFP "SLAM" principle comes into play (link below).

Along with Kim's link above, I agree you should do a good water exchange to lower your CYA. Before you fill the pool back up, make sure you have your own TF-100 or Taylor K-2006C test kit on-hand. You'll need to SLAM your pool to eradicate the residual algae, and the proper test kit is absolutely key in doing that. Until then, don't add anything else to your water, especially pool store products. We aim to save you $$$ through simple chemistry and products that won't break your bank. Regular bleach will be your weapon of choice from now on.

It's great you found us. We can help guide you with proper testing and a few simple TFP principles, most of which you can find our Pool School page and/or links below in our signatures. Speaking of which ... don't forget to update your signature as well when you get a moment. Nice to have you with us.