Another Algae Fight - Am I doing this right?

[Airren]

Water is green & cloudy and chlorine levels were very low. Been reading here and am trying to clean this up. We had been using a chlorinator for years and I think it might be time to stop it. Fiberglass 9000 gallon pool. Anyway, here were the readings from yesterday.

FC: 4ppm
CC: 2ppm
TC: 6ppm
PH: 7.2
TA: 310 ppm
CYA: Too high to tell!
CH: Negative

We drained some water, then put in 5 5.38L bottle of bleach(6%) and turned the chlorinator off.

FC: 2ppm
CC: 1ppm
TC: 3ppm
PH: 7.2
TA: 260 ppm
CYA: Too high to tell!
CH: Negative

About to put in a bunch more of the 5.38L bottles of bleach. Any recommendation on how many? Am I doing this right?

[Watermom]

Yep. Time to turn the chlorinator off! Who knows how high your CYA actually is. To clear this up, you need to shock the pool up to about 25ppm and try and hold it there. Test as many times a day as you can and each time, add enough bleach to get back to 25ppm. In a 9000 gallon pool, each quart of 6% bleach will add 1.7ppm and each gallon (4 quarts) will add about 6.7ppm. Use that as a reference to figure out how much bleach to add each time you test. What kind of kit do you have? You can force a kit go test higher than 5 with a dilution method described here: Testing Without a Good Kit (This is not super accurate and not meant to replace having a better kit, but better than nothing.)

If you don't have a good kit, you're gonna need one. With a CYA like that, you'll always have to run higher than normal chlorine levels and other kits aren't going to be able to read past 55ppm. The one we recommend is the Taylor K-2006 or 2006C (same kit, larger bottle of some reagents). If you buy it through the Amazon link in my signature, the Pool Forum makes a little money on the sale which helps us keep this form online. Only buy if the seller is Amato Industries, however. Some other sellers are substituting the K-2005 which you do NOT want. If Amato isn't listed, wait a day or two and try again. They seem to restock pretty quickly when they sell out.

Hit it hard with the bleach and sustain the high levels. Your TA is too high. Read the following two guides for more information to help you deal with that.

Lowering Alkalinity Step-by-Step

Using Muriatic Acid Safely

Run your pump 24/7 and clean your filter as necessary. (What kind of filter do you have by the way?)

One last thing. Do us a favor, please. To make it easier for us to help, if people will create a signature line with their pool specs, it keeps us from having to reread through posts to find out basic information. You can create a signature by clicking on 'settings' in the upper right-hand corner of the homepage. In your sig, please put type of pool, volume, type of filter, size of pump, whether or not you have a SWCG or any water features and the fact that you do or do not have a K-2006. Thanks!

Hope this helps. Keep us posted of the progress and let us know if you have any further questions.

[Airren]

Hi, thanks for responding. I am using the Taylor K-2006 and we have the Hayward sand filter.

TA too low? I thought TA needed to be somewhere around 120? We're at 260ppm right now.

The FC is now over 25ppm and we're holding there. Need to get more testing reagent. I will use the dilution method and try to find out what the real CYA is.

This site is so utterly useful, in the past 4 days I've learned so much!

[Watermom]

OOPS! My bad. Meant to say TA is too HIGH. I went back and made the correction in my previous post. Sorry 'bout that but thanks for letting me know so I could fix it!

Add a bit to your signature line ----- size of pump if you know it and also the fact that you have a K-2006 kit. Thx!

[Airren]

OK, we've been holding at 25ppm for about a day and a half now. Water is getting clearer - hurrah! I guess we should hold another day at these levels? PH is now 7.4.

Thanks again for your help!

[Watermom]

Yep. Stay at 25ppm.

[Airren]

Still there, even clearer tonight. I do notice there are some orange stains on the steps and sides. Metal? To hit with Citric Acid? Leave alone? Not even sure how to test for that.