Hot Tub?

[savdoc2]

Hi folks,

This may not be posted in the right place, so move it if need be.

We have a stand alone hot tub that we haven't used for nearly 3 years (long story). Well, my husband recently got it working. We used to have a ozone generator on it, but no longer do. We never used to test the chemicals, but I "think" I know better now. I am using Ben's kit for my AG pool and I am guessing that I can use the same kit for testing the hot tub water. What I don't know is what the propers levels should be and how do I go about adjusting the levels. My guess would be to use the BBB theory. Am I assuming correctly? Currently the levels are:

ch = 0
pH = 8.2 or higher
alk = 200
calcium = 100
cya = 0

thanks

[RavenNS]

Yes, The BBB is just fine for Hot Tubs;
however, you may want to substitute BROMINE for Bleech.
Bromine is more stable at higher temperatures ( doesn't dissapate as quickly), so it is used more often in hot tubs & stand-alone spas. You can use either, so if you can get bleech really cheaply, you could go that method.

you wanted to know what levels your testing should be:
you may want to check with the manufactor of your tub as they might have specific levels required to maintain warranty,
however this is what is generally accepted:

PH : Between 7.2 to 7.6
TA ( alkalinity) Between 80 to 120
TH ( total hardness) Between 100 - 200
Bromine: 3ppm to 5ppm
TDS ( total dissolved solids): Under 1500ppm

( I prefer to keep my bromine up around 10ppm, but that's considered "high" by industry standards)

You can check throughout the pool forum for information on how to correct your levels using BBB.

( first chance you get, you need to get the sanitizer levels up)

Good Luck & Happy Tubbing

[waterbear]

IF you decide to use bromime you need to keep tabs on the pH since it tends to make it drift downward. You will also find that your ALK might depleat over time. The best oxizider for a bromine system is bleach, btw. don't waste your money on MPS (non chlorine shock). Bleach works better. All bromine systems need chlorine or another oxidizer to work properly.
Don't worry about TDS, just remember to drain and refill on a regular basis depending on the amount of use the tub gets.
Chlorine is equally effective in a hot tub. Keep your FC at least 4 ppm up to as high as 10 ppm. Most people keep it in the 4-6 range but if the tub gets heavy use you might want to keep it as high as 8 ppm on a regular basis. If the tub is exposed to sun and is outdoors you will need to add CYA to the water if you decide on bleach for your chlorine source.
You will probably find that dry acid (sodium bisulfate) is easer to use in the tub since the amount of muriatic acid you might need if you need to lower pH or TA is very small and is ususally on the order of teaspoons and tablespoons. Borax and baking soda are the other things you will need, just like in your pool.

[savdoc2]

Thanks.

The tub gets very little sun, it is in a screened in porch. This tub has no warranty - it is at least 15yrs old.

I was trying to figure out how much acid to add to bring down the pH and I think I am just going to use bleach as my sanitizer - I already have it for my pool anyway.

Thanks again.