yellow algae

[Watermom]

Thank you for filling in the Pool Chart for us. Are the tabs you are using trichlor? If so, I'd suggest that you stop using them and just stick with the liquid chlorine. The tabs are stabilized and will cause your CYA to continue to rise and yours is already high enough.

With a CYA of 60, you need to keep your chlorine level between 5-10 all the time and your shock level will be 20. (Take a minute and read the Best Guess Chlorine Chart in my signature above.) So, I'd suggest shocking your pool and try and keep it at shock level until you can go from sundown one evening until within two hours or sunrise the next day without losing more than 1ppm of chlorine and your CC reading is no higher than 0.5ppm and your water looks clear. Then, keep the chlorine high one extra day for added insurance and then you can let the chlorine drift back down but don't let it go lower than 5ppm.

For reference and to help you figure out doses of bleach to use, in your pool, each gallon (4 quarts) will add about 2.7ppm of chlorine. (Is that what you are using when you say liquid chlorine? If you are using liquid pool store chlorine, what concentration is it?)

Your pH and alk are fine.

Hope this helps.

[ronjorob]

i have 3 tabs tricor in pool now.do i shock with liq or super shock powder. i use 10% concenrtate chlorine. isnt the powder shock tricor & will raise cya. thanksu.

[Watermom]

The shock powder might be dichlor or it might be cal-hypo. Look at the label and tell us what the ingredients are. After the trichlor tabs that are currently in the pool dissolve, don't put any more in. You don't want your CYA to get too high. If you are using 10% sodium hypochlorite, then each gallon (4 quarts) will add about 4.5ppm of chlorine.

[ronjorob]

powder is tricor. so i wont use it. so if chlor level is 7 &i add 2 gallons liq it brings it up to shock value of 16?

[Watermom]

Not quite. Shock level for a pool with a CYA reading of 60 is 20ppm. If you add the third gallon it would bring it up to shock level.

[ronjorob]

added 3 gal chor then added another 24 hrs. later . still got algae. now not sure if it is algae or stain. i goofed in my chart i have a ig pool with gunite pebble tec.

[aylad]

You need to hold that shock level until the algae is gone, testing and adding more bleach as needed. Letting your chlorine yo-yo up and down like that won't ever let you get ahead of the algae and kill it.

Janet