yellow algae

[ronjorob]

been shocking pool like u recomended & still have alge or stain.water is crystal clear. been adding 3gal of 10% chlorine everynite. have a reading of over 23 ppm. next morn reads 20ppm. combined chlor is o. all my other chemicals r right on. lose about 10ppm chlor thoughout the day.

[aylad]

If you're still losing 3 ppm of chlorine overnight, then you're still fighting something in the water and need to maintain the shock level.

Janet

[PoolDoc]

still have alge or stain.water is crystal clearhave a reading of over 23 ppm. next morn reads 20ppm.

In your case, it will probably take 25 - 30 ppm sustained over a week or so, plus brushing.