Non-Chlorine or Chlorine Shock

[DCarlson91]

So over the last week I had noticed that the deep end of my 16x32 pool had become a little murky, after testing it i realized the chlorine had gone now to almost nothing. I use a floater with three inch pucks to supply it. I refilled the floater and added a granular cal-hypo to try and quickly bring it back. I tried another shock the following night after seeing little improvement. I realize now that I may not have been adding enough to actually break through. I used the water treatment lab at my place of work to get a good test result today and realized my free chlorine was almost zero (.2) and my total had risen to almost 4. I'm wondering if I should add a non chlorine shock to bring the total chlorine down while just letting my floater slowly bring the FC back up, or if I should do another cal-hypo shock just stronger. (I added a little over 1kg the second shock and 700g the first)
FC-0.2
TC-4.1
pH-7.1
TDS-620
Calcium-180
Thanks!
(Called multiple pool technicians and heard vastly different answers)

 

[ajw22]

Welcome to TFP.

Where is UG1995309 that is listed in your location?

Your water treatment lab is not testing all we need for pool chemistry. Specifically CC, TA and CYA. I suggest you review ABCs of Pool Water Chemistry.

Shock is not going to fix a murky algae problem. You need to follow the SLAM Process with sufficient level of chlorine. You are going to need your own test kit like the TF-100 Test Kits or the Taylor K-2006C for the frequent testing the SLAM Process requires. You should also consider the XL Option since you will go through a lot of reagents and the Speedstir Magnetic Stirrer.

 

[DCarlson91]

Welcome to TFP.

Where is UG1995309 that is listed in your location?

Your water treatment lab is not testing all we need for pool chemistry. Specifically CC, TA and CYA. I suggest you review ABCs of Pool Water Chemistry.

Shock is not going to fix a murky algae problem. You need to follow the SLAM Process with sufficient level of chlorine. You are going to need your own test kit like the TF-100 Test Kits or the Taylor K-2006C for the frequent testing the SLAM Process requires. You should also consider the XL Option since you will go through a lot of reagents and the Speedstir Magnetic Stirrer.

Hey there,

I must have forgot to add my TA-130. My CC would be almost 4.0. To be honest I have never really looked into the CYA, nor have I added it. From my understanding it is mostly to prolong your chlorine from the breakdown of the sun. I don’t really have this problem as the pool is located indoors. Thanks for the reply and the good reviews! Gonna be getting a better test kit as well

 

[ajw22]

CC of 4 indicates an algae problem.

If you are using trichlor tablets in your floater then you have been adding CYA. You likely have too high an accumulation of CYA.

Please put details of your pool in your signature including that it is an indoor pool. It helps us give you the correct advice.

 

[Etchase]

If the three inch pucks you have been using are trichlor, they add CYA to your water. This can add up quickly. It does extend the half life of the chlorine from UV degradation from the sun. But it also greatly reduces the level of available chlorine for killing algae. You should check your CYA levels if you have been adding trichlor, and also be careful with using calhypo and trichlor at the same time. They don’t play well together. If the pucks you are using are calhypo, none of what I said should be a problem.