No Chlorine & Algae

[Rebel86]

Have an inground saltwater pool. I have used a pool service company since i have owned my home, but with COVID have had to start taking care of it myself. If anyone could help steer me in the right direction I would greatly appreciate it.

Saltwater Inground Pool approx 17,500 gallons

Pool is green with algae at the moment....

Tested water chemistry with Taylor K-2006 kit and here are my readings.

PH - 8.0
Free Chlorine = 0
Total Alkalinity - 70ppm
Calcium Hardness = 140 ppm
CYA = 40 ppm

Salinity read 3000ppm on my Hayward Aqua Plus

I thought the salt was far off from that reading so i purchased the Taylor K-1766 test kit and performed the test:

Salanity = 4,600 ppm

It's also worth mentioning that my hayward salt cell is 6 years old and i thought that may be the problem. I purchased a brand new salt cell but have not installed it yet as i thought the high salt levels may damage the cell.

If anyone could help me with balancing the water chemistry, getting rid of the algae, and when to install the new salt cell i would greatly appreciate it.

Thanks much!

 

[Rebel86]

Correction CYA=40ppm

 

[mknauss]

Follow the SLAM Process. Lower the pH to 7.2 and follow the process.

Once you pass the three criteria, we can work on the SWCG.

 

[YippeeSkippy]

As an addendum to what Marty said- anytime you are unsure of the cell's performance, don't let the pool go without chlorine and risk algae.
Step in and use Liquid Chlorine and PoolMath to tell you how much to add to get the result you need.

Maddie

 

[duraleigh]

Please read "The "ABC's of Pool Water Chemistry" up in Pool School. You must start with the basics and understand the function of chlorine before you can understand much of the above

 

[Rebel86]

Thank you for all the responses! I have performed the SLAM process and lowered the PH Level. Pool algae is mostly gone as i have had pump running for last couple of days full time. I tested the water this morning and below are my numbers. Please let me know where to go from this point? I still have my new salt cell which has not been installed yet. I am fairly certain my old one is bad as it is 6 plus years old and my salt readings on the hayward system shows 3000 ppm. Any advice would be very much apreciated!!

Salt test with k1766 kit - 4200 ppm
Free Chlorine - 7.2 ppm
Combined Chlorine - 0.6 ppm
PH - 7.0
Alkalinity - 70 ppm
Calcium hardness - 130 ppm
CYA - 35 ppm

Thanks again for the help!!

 

[JJ_Tex]

Make sure you read the SLAM article and follow the advice. You need to get your FC up to SLAM level (16 for a CYA of 40) and keep it there until you are algae free and meet the 3 criteria to end a SLAM. That will likely take several more days.

 

[Rebel86]

Thanks for the response can you please hyperlink the slam article? I assume you are saying i need to continue to add (increase) chlorine to get the level up to 16 with a cya of 40 ppm? How do i calculate how much more chlorine to add?? Thanks for the help.

 

[JJ_Tex]

You got it. The SLAM is basically keeping your FC at a certain level to kill everything growing in your pool.

Here is the SLAM article. Also if you look at my signature, it has the FC/CYA chart that tells you how much FC you need for your CYA, both for a SLAM and just a regular maintenance.

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

 

[setsailsoon]

86,

You are getting lots of great help from our experts. It will help you and them if you can please fill in your signature. This way you won't get all the basic questions before you get real answers and our volunteers can be more effective with their time. Here is how to do it.

The problem you are experiencing is not uncommon at all. As you work through the solution with our experts you are going to learn a huge amount about maintaining your pool successfully. When you're done you will pretty much be on autopilot. And our experts will always have your back for any future problems.

Good luck! we have a great video that you might want to look at. I have posted it below.

Chris