dpt powder doesn't make water turn pink

Quote:

Originally Posted by marciastz

I opened pool about 2 weeks ago after a few days had sparkling clear water and everything seemed fine. Everything was going along fine, adding a little bleach every day, slowly raising total alkalinity, and successfully raised ph to 7.4. Have had lots of little swimmers. I got lazy, didn't open the cover for 2 days, opened it last night to cloudy water, can barely see the bottom. Tested with my little poolside tester, and showed no chlorine, which I expected it to. I'm very low on liquid bleach, so I put in 3 lbs of dichlor, but it looks the same or worse this morning. Backwashed the filter and got my good test kit out and tested, cya-50 ph-7.2.----DPT POWDER WON'T TURN THE WATER PINK!! I have never had that problem. Powder is from last year but is very light grey and looks in really good shape. What is this telling me??? Added 3 more lbs of diclor this morning. My pool is 25000 gallon IG vinyl. I'm going to pick up some bleach today (price is sure higher this year). Can you advise how I should proceed??

The powder could be bad but my first guess is that you are using up your chorine pretty fast fighting the algae. I would use bleach instead of dichlor and get the FC up to shock level (20 ppm) and keep it there until the chlorine level holds over night. You will keep using up all the chlorine until the algae is gone so you will probably need a lot of bleach. You will need 8 gallons of 6% bleach to start and probably at least that much to keep it at 20 ppm for another day.

Using dichlor will continue to add CYA which will make it harder to kill the algae. You are at a good level now but that can quickly climb when trying to shock the water with dichlor. BTW what are your other levels?