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Looking for a little clarification please water chemistry


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First off let me give you the specs and current water parameters.

Clearwater 475 gal. With ozone & uv. 98° 

Typical user load is 4-5 days per week, 2 people, 1 hr.  This is the first water fill and it has been running for approximately 3 months.

Using Taylor K-2006 test kit

Currently using a mineral stick in filter 1.

I've been using 6% liquid bleach since my cya hit approx 35ppm.


CH 180

TA 60

FC 6

TC 1

I have had my TA @ 120+ for a while and have constantly Fought with pH rising to and above 8.0.

Finally decided to read nitros bleach method and look up the acronyms that I did not know. Using muratic acid( lots of it) I have brought my TA down to the point where the PH settled at 6.8 . Boric acid is showing up tomorrow and I'll be adding 32oz (weight) to get a 50ppm boric load for buffering the low TA. 


I keep reading different things about mineral sticks, whether or not to use them and why. There seems to be a caveat to every situation. 

How long I can run the water before needing to drain and fill it? What are the indicators that I need to look for  when it comes to water change? Water prices in my city are absolutely insane, so I'd love to limit water usage as much as possible. 

My CD has been insane, but my parameters have been all over the place so I'm not sure if it's the ozone or something else entirely. I've been adding around 3/4 cup of bleach  after our nightly soak.By the next evening it's down to .5 ppm or less. 

Also, how often do I want to shock? I have non chlorine shock,or bleach available.. 


I really appreciate your time!






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Your insane chlorine demand is an indicator that you need to change your water. Read Nitro's post on Chlorine Demand and follow his Decontamination Procedure. I recommend using Ahh-Some and before draining the tub, super-chlorinate. This will save you 475 gallons of water.

Don't add the boric acid until after you decontaminate, drain and refill. I have a 450 gallon spa and add 17.2oz of boric acid to get 50ppm borates. You might want to recheck your calculations.

If you need to lower TA, follow Nitro's procedure for Lowering Total Alkalinity. You will need to aerate to bring your pH up to 7.4 to 7.6 (6.8 is much too acidic).

Regarding mineral sticks (e.g. Nature2), I don't believe there is much benefit using them unless your'e using MPS instead of chlorine.

As long as you keep your free chlorine from falling to zero for extended periods of time, there is no need to "shock".

Hope this helps.




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