ray_c Posted July 22, 2009 Report Share Posted July 22, 2009 I have noticed the chlorine level has been staying high in the pool despite not shocking or adding tabs to the chlorinator in a couple weeks. I have been waiting for it to come down, but it just is sitting between 8-10ppm. I also use nature 2, so I usually keep it much lower. The pool is clear, filters 8 hours a day, and is used at a moderate level. I confirmed the reading with test strips and by taking a sample to the pool store. Is there a reason why a chlorine level would stay high for a long time like that? thanks, Ray Quote Link to comment Share on other sites More sharing options...
chem geek Posted July 23, 2009 Report Share Posted July 23, 2009 Do you have a pool cover or is the pool not exposed to direct sunlight? Have you been using any non-chlorine shock (potassium monopersulfate, MPS)? Quote Link to comment Share on other sites More sharing options...
ray_c Posted July 23, 2009 Author Report Share Posted July 23, 2009 Do you have a pool cover or is the pool not exposed to direct sunlight? Have you been using any non-chlorine shock (potassium monopersulfate, MPS)? The pool is exposed to sun. I do not use a cover during the season. I do use MPS as part of the weekly routine. Quote Link to comment Share on other sites More sharing options...
chem geek Posted July 23, 2009 Report Share Posted July 23, 2009 MPS will usually show up as Combined Chlorine (CC) though soon after addition or at very high levels it can show up as Free Chlorine (FC) as well. You didn't say whether the chlorine level was FC or Total Chlorine (FC+CC). So perhaps the MPS has built up and your pool is quite clean with little organics to oxidize. Your Cyanuric Acid (CYA) level in the pool may be very high from continued use of Trichlor since for every 10 ppm FC added by Trichlor, it increases CYA by 6 ppm. High CYA levels can significantly slow down breakdown of chlorine from sunlight. So between the remaining residual tabs in the chlorinator and the weekly MPS, you might have been holding oxidizer levels which is probably what is getting measured. Even so, this does seem strange. Quote Link to comment Share on other sites More sharing options...
RMS Posted August 10, 2009 Report Share Posted August 10, 2009 I have noticed the chlorine level has been staying high in the pool despite not shocking or adding tabs to the chlorinator in a couple weeks. I have been waiting for it to come down, but it just is sitting between 8-10ppm. I also use nature 2, so I usually keep it much lower. The pool is clear, filters 8 hours a day, and is used at a moderate level. I confirmed the reading with test strips and by taking a sample to the pool store. Is there a reason why a chlorine level would stay high for a long time like that? thanks, Ray I agree with chem geek, but lay off the MPS and try using Calcium Hypo. Keep the cover off, and if that doesn't work, you may want to add Thiosuplphate to get the chlorine level down. http://www.clean-pool-and-spa.com/swimming...l-chlorine.html Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.