Water is clear, with greenish hue but HAVING PROBLEMS! help please!

[Mrtallpaul]

Hello all, would love some help as I am VERY frustrated at this point. Pool is one year old and starting this spring have had a lot of trouble keeping balanced and algae free.

Pool basics: 17,200 gal chlorine with Pentair Clean and Clear Plus 520 ft filter system. Pebble tec lining. Running filter 11 hrs /day in Houston TX. In-line chlorinator with 3" tablets.

Pool is currently clear but has a green hue. I have had issues with algae and did some Yellow stuff algae treatment (and a second time in three days). Used pool brand 40% algeacide a few days after that. Still getting some algeacide growth.

Problem is my chem readings are crazy. Was low (7.2) on ph so I added 3 lbs of household baking soda. Another reading two days later shows it only at 7.2. Since so many issues, I want to raise a little and add two more lbs. 1 day later reading now is 7.0?? Also chlorine reading were at 0 this am (have been low and I have been shocking a lot with the algae treatment) so I put in 2 cups granular chlorine. Waited 5 hours and had water tested again, still at zero.

What do I do? I'm obviously doing something wrong...

Current chem readings: FAC-0, TAC-0, CH-270, CYA-40, TA-100, PH-7.0

Please help!

[aylad]

Hi, and welcome!!

The algae growth you're having is because you're not keeping your chlorine levels high enough for your CYA level. With a CYA of 40, you will need to shock your pool (we recommend plain, unscented bleach for this) up to 15 ppm, and hold it there by testing and adding more bleach as needed to hold that 15 ppm level until the algae is all gone. Once you can go from sundown one night until just before sunup the next morning, then you can let your chlorine drift back down to the 3-6 ppm range, but no lower, otherwise you'll end up with algae again.

When your pH is low, you add Borax to raise it--not baking soda. The baking soda is used to raise your alk, which is fine where it is.

How are you getting your chem readings--are they drop-based or strips? If you don't have one, do yourself a favor and get your own drop-based test kit. Using pool store readings, which are designed to sell chemicals, is an expensive, and often not reliable, way to get your water tested. We recommend the K-2006 kit (see the link in my sig), which will test for everything you need, accurately, and help you take control over your pool.

Don't put anymore algae treatment or cheap algaecides in the pool--they're just creating another chlorine demand for you to overcome, and you want all your chlorine to be available for the algae.

Again, welcome to the forum!!

[Mrtallpaul]

Thanks for your help. I'll have to get some borax - don't have that.

I just added a bunch of bleach to start this process. I have a drop system chem reader. Chlorine only goes up to 6 ppm, so I'm not sure how much to put into get to 15 and am unsure how to keep it there. Is the other drop test kit able to read up to 15ppm? Any other thoughts as to how much bleach is needed? Estimate based on pool gals?

Thank you for your help. The pool is on the brink of out of control and I want to reign it in.

[Watermom]

The K-2006 kit that Janet encouraged you to buy will read high chlorine levels up to maybe 50? Can't remember. Until you can get the good kit (and I agree that you should), you can force your kit to read higher by using a dilution method. You do lose some accuracy with dilution so it is not meant to replace getting the good kit.

Testing Without a Good Kit (http://poolsolutions.com/gd/how-to-test-your-pool-without-a-good-testkit.html )

In a 17,200 gallon pool, each quart of plain, unscented 6% bleach will add just about 1ppm of chlorine. Use that as a reference to help you figure out doses of bleach to add. How to keep it at shock level? Test frequently and each time add enough bleach to get it back up to 15ppm.

Hope this helps!

[PoolDoc]

membership upgraded. -ben

[Mrtallpaul]

Thank you.