Chlorine / Bleach smell but Combined Chlorine tests at 0

[kramsey]

Hi Everyone,

We've noticed the last week or so that our pool is smelling of bleach much more than it has previous years. I googled it, and it seemed that this is usually due to combined chlorine being too high, requiring a shock. But, when I just tested my water using my Taylor kit the combined chlorine is reading as 0. Is there another reason why the water would smell like chlorine?

Here are my pool details:

25,000 gal. pool in Monroe, CT
FC = 2
CC= 0
CYA = When I use the test on the taylor kit the black dot never actually disappears, so I think it is very very low?
TA= 80
CH= 190
PH = 7.6

I have been using the liquid bleach method promoted here for the last few years. It worked perfectly, but it was just too much of a hassle to find the 12% bleach bottles, and to add it daily. So, I switched back to the pucks in a chlorinator (I know, it may be more trouble in the end but I figured I'd give it a try!) Pool has been open for about two weeks using this new system. Could this be the reason for the smell?

Thanks for your help!

 

[OTPirate]

Hey! The TFP method does not recommend pucks because they add CYA. I am surprised your test is showing no CYA even though you have been using pucks. If bleach worked perfectly before, why don't you continue using it? If you can't find 12%, use the 8.25% found in many places. The "smell of chlorine" indicates an unbalanced pool, and you can have 0 cc and still have algae in the presence of low CL like yours. Good luck!

 

[kramsey]

Hey! The TFP method does not recommend pucks because they add CYA. I am surprised your test is showing no CYA even though you have been using pucks. If bleach worked perfectly before, why don't you continue using it? If you can't find 12%, use the 8.25% found in many places. The "smell of chlorine" indicates an unbalanced pool, and you can have 0 cc and still have algae in the presence of low CL like yours. Good luck!

Thanks for your reply! It was just too many bottles and too many pieces of clothing ruined by the liquid bleach splattering. I know I may eventually switch back, but I figured since my cya is so low anyway it wouldn't be much of a problem this season to use the pucks.

So you think I could still have some residual algae that is causing the problem? I will do an overnight loss test. After I SLAM the pool should I try to maintain a higher FC? I guess I should follow the CYA/shock chart for that right? Thanks again!

 

[OTPirate]

Morning! You should always maintain the recommended levels of CL for your pool, and your CL is low. One problem with using pucks is that you don't know exactly how much CYA you are adding to your water, making it impossible to use the CYA/shock chart.