New Pool High CC reading

[Tumby Bay Indoor Pool]

We started using our new indoor pool on our farm in late December. Our pool installer got all our chemical levels right (so I believed) and we got swimming. Friends soon started to complain of sore eyes and we checked our water at a local testing place and found we had high CC (1.5ppm) after much reading I learnt that this creates the bad smell which we had and the sore eyes.
We were told to put in 10l of liquid chlorine and run the pump for 1 hour. We have pretty much no CYA (2ppm) as it is indoor (after reading info on this site I think we will get it up to 20ppm to help reduce available chlorine levels).
Since adding the chlorine our FC has gone up to 9.34ppm and our CC hit a high of 2.76ppm. It is now at 1.86ppm after adding another 10l of chlorine after topping up the pool with rain water. Our FC is over 10ppm (I could only stick test today), the CC just is not coming down, the water looks clear, it doesn't smell, but it does hurt our eyes if we put our heads under.

Why would a new pool that is only used by family have such high CC when we run our SWG 6 hours a day on a 3 or 4 setting.? What can we do to stop it getting this high again?

Why won't the CC come down even though I am pumping liquid chlorine in to keep FC near 10ppm?

I ran the pump only for 24 hours and we have left all windows and door open to ventilate the room and the stick reading has not moved.

Our salt is 5100 ( 100 above recommendation)
Our Ph is around 7.6
Alkalinity is 103ppm

I will get a proper test done again when I go into town but our stick test shows FC and TC and both are very high still tonight.
Anybody can help please let me know why you think we are having this problem.

55,000litres, fibreglass, sand filter pump, austral VX SWG, indoor, Zane PC5 solar pump, manual pool vacuum cleaner

 

[JasonLion]

Welcome to TFP!

It is common to have CC problems with indoor pools. In an outdoor pool sunlight helps get rid of the CC, but you don't have that with an indoor pool.

One common solution is to use MPS in addition to chlorine, which is better at breaking down some of the persistent kinds of CC than chlorine.

 

[Tumby Bay Indoor Pool]

Thanks, I will check levels tomorrow and get some MPS if our CC's are still high. After looking at all the posts on Ozonej think maybe we would benefit from that with an indoor pool and little children that are sensitive to high chlorine.

 

[Tumby Bay Indoor Pool]

Also, if we do use MPS to get rid of the CC, how long will it take for our FC to come down from 10ppm? Is there any way of speeding this up? Should we turn off SWG and just run pump?, Would adding CYA help? Any other suggestions?

Thanks

 

[JasonLion]

There are chemicals to lower the FC level, thiosulfate for example. However, I would wait on that until we clear up a few questions and see how quickly FC drops with the SWG off.

Adding CYA to around 20 would help keep CC from going up as quickly, and prevent some side effects/problems from very high FC levels. With zero CYA, swimming is strongly not recommend with FC that high. Without CYA you shouldn't swim with FC above 5, and even 3-5 will cause accelerated breakdown of swimsuits. With CYA swimming at that FC level is no problem at all and the swimsuit issue is eliminated.

Yes, turn off the SWG until the FC level comes down. And when you turn the SWG back on, turn down the percentage setting so it doesn't just drive the FC level up too high again. With an indoor pool you need to actively manage the SWG so that the FC level stays in the recommended range. It is very easy for a little inattention to result in a very high FC level.

I recommend UV instead of ozone. Either one will help keep CC under control, but a malfunctioning ozone system can cause respiratory problems, which can't happen with a UV system. That kind of malfunction is rather rare, so just a minor point, but enough to swing me to recommend UV rather than ozone.

 

[Tumby Bay Indoor Pool]

Thanks again, I will look into UV as well, and for now we will add CYA to lower available FC and MPS to lower the CC and hopefully after that the pool will be swimmable again! Did I read somewhere that the MPS shows up as CC if we test afterwards?
I am sending my husband now to get all this stuff!

 

[JasonLion]

How MPS shows up on the test depends on which test kit you are using. A DPD chorine test will show MPS as CC. But a FAS-DPD chlorine test will usually show MPS as FC (there are some exceptions however).

Often, the MPS will dissipate in a couple of hours, so the testing issue isn't always an issue. There is also a special reagent you can get so you can prevent the MPS from affecting the test.