Low chlorine reading

[sabres07]

If you don't test, you'll suddenly end up with extremely high chlorine levels, and with no CYA in the pool you're liable to end up with a bleached liner.

OK, I will stay the course. I do have a 30 for CYA. Does that change your opinion on what I should do?

Thanks for all of your help so far.

[PoolDoc]

I do have a 30 for CYA. Does that change your opinion on what I should do?

No.

[sabres07]

So I tested my water this morning and my ph went from 7.8 down to 7.2 overnight. I did not add any acid or anything else to the water. What would cause the ph to drop like that????

[PoolDoc]

Did your chlorine also drop? When chlorine is used up, the end product is acidic.

[sabres07]

Yes, I dumped in 7 gallons of bleach at 8 PM and tested the water shortly after. I finally had a high chlorine reading. At 11 PM I retested and the chlorine was at 0 and ph was at 7.8 or so. This morning I tested the water, and chlorine was still 0 but ph had dropped to 7.2.

My plan is to put 7 more gallons in tonight at 7 PM, and then re-test at 11 PM to see if it held or not. If it dropped again, I will reapply 7 more gallons of bleach. I am trying to break this ammonia or bacterial trap I am in. I was just wondering about this ph drop I had and how I should handle it in the middle of this trap I am in.

At 7:30 PM I added 6 gallons of bleach, chlorine readings were very high. I have retested every half hour since then and the chlorine seems to be holding. The ph however is dropping. It is at 6.8 now at 9:45 PM. Should I address this or should I just stay the course and keep the pool in shock mode?

[PoolDoc]

If you have some borax, I'd go ahead and add a box. It's not a crisis, but you don't want to leave the pH below 7.0 indefinitely.

[sabres07]

So after testing the pool at 11:30 PM last night, I was showing a reading above 5 ppm (as high as my test allows) but it was not as yellow as when 6 gallons of bleach was added at 7:30 PM. I added another 6 gallons of bleach. At 6 AM this morning, I tested and re-added 6 more gallons of bleach. Ph seems to be spiking when chlorine is added, as expected, and settles in at 7.2 hours later. Water is still cloudy, though.

I think I have turned the corner in my battle with whatever is causing my chlorine demand. Now I need a test kit that reads higher than 5 ppm chlorine. Does the 6 way HTH kit from Walmart read that high? I can get one today, otherwise I will order one from Amazon.