Need help - New Spa and chemical balance - Cloudy water

[jdskycaster]

I have read through many posts but want to ask a couple questions. I have a 500 gal. spa with ozone. Started up 3 weeks ago and have been using it about every other day. I have been testing the water daily and it has been clear until now. My regimen has been - Nature 2, Daily Dichlor (when needed to keep FC at 3ppm) also after each use (.25 oz/ bather/30 min.) and then weekly shocking with MPS - 4 oz. along with 2 oz. of scale inhibitor. System is set for 4 - 2 hour circulation cycles. Been keeping the water around 98 degrees. I opened it today and was surprised to see cloudy water as it has been perfectly clear so far. Did a quick FCL test and it was about .5 so I shocked it with 4 oz. of MPS and also added 1 oz. of Dichlor. Here are my current readings:

FCL 1.61
TCL 12
PH 7.3
CH 220
CYA 110

I know my CYA is high - should I just dump some of the water and start to rebalance?

Should I dump all of the water and start over? 3 weeks seems pretty quick to have to change 500 gallons.

If I do dump it to lower CYA should I start out with Dichlor and then switch over to Bleach when CYA gets to 20?

It seems like I used a lot of Dichlor over the first 3 weeks (almost a complete 2lb. bottle) and CYA just steadily climbed until I reached the current level. Bleach should help with that but will bleach work as well as the Dichlor?

I appreciate any input here as I am new to this spa thing. The pool seems much easier to me at this point :|

Thanks,

JD

 

[JasonLion]

If I do dump it to lower CYA should I start out with Dichlor and then switch over to Bleach when CYA gets to 20?

This is the key. You let CYA get too high, so you need to replace water. By managing how much dichlor you use you can control the CYA level and go much longer between refills.

 

[jdskycaster]

Thanks Jason.

So to control CYA should I be using Bleach instead of Dichlor at each use and also to maintain FCL at 3ppm? Continue to shock weekly with MPS? I was getting confused because somewhere I read that I should only be using Dichlor as a primary sanitizer in a spa - no bleach due to the high water temps.

Best Regards,


JD

 

[JasonLion]

Bleach and dichlor both contain chlorine and, ignoring the CYA added by dichlor, both sanitize the spa in the same way. By switching from dichlor to bleach at the right time you get control over the CYA level, which is very important.

Chlorine does not work as easily in a spa as it works in a pool, but it does work. Some people prefer to use bromine because it is more stable and less work at spa temperatures.

MPS is fine, works the same with either bleach or dichlor.