Trouble Balancing Water/high Ph

[salachic]

Hi. We are relative newbies.... got the hot tub just before xmas. At first we had trouble with the bromine but I think we have that figured out. We now have the taylor kit and use that as well as the occasional test strip. I am jealous of the ppl that say they only have to test every couple of weeks etc because they have their system all figured out. We practically have to test daily and ours is always out of whack.

Our "average" numbers look something like this:

Hardness: 150

TA: 70

Ph 8.0

Bromine 5.0

I think the PH is very high, so we put in the stuff to lower it, and the very next day it is back to 8.0. We do not have a heavy bather use.... sometimes only 1 person got in that day, sometimes none, and the PH goes right back up.

A couple family members have developed a rash that appears to be from very dry skin (definately not the bacterial kind of rash). Would this be caused by the high PH? How do I keep it down (or balanced)?

I plan to refill and start over at some point, but we are in the northeast and and cannot do that at this point due to the weather.

Thanks for any pointers.

[chem geek]

If you use aeration jets, then that will cause the water to rise in pH faster. To minimize this, you can lower your TA further to 50 ppm and also add 50 ppm Borates (usually from boric acid or from a separately added combination of Borax and acid).

[salachic]

Yes, we use the jets and aerators often. I will look into Borates.... never heard of that one before.

Also, I've been reading the Bromine for Beginners article. We are thinking of switching to bleach to shock instead of using the OxyShock that we have. But the articles on here mention that an unbalanced spa can "reduce the effectiveness of the bromine". Does that mean that it's not really working well even if the Taylor test kit says my bromine is at a 5? (in which case I would not know it's not really doing the job?) Or, if my TA/PH imbalance were reducing my bromine effectiveness then my test kit would show a lower bromine number?

Also, someplace I read that after shocking it is not uncommon for bromine #s to jump alot.... say from 2 to 10+??? This is normal? It is supposed to go back down on its own... but we should wait (a day or 2) until this happens before using? Or is it ok to wait X period of time and use it even if the # is still high? What are possible effects of using a tub with a high bromine?

Thanks.

[chem geek]

Actually, the OxyShock, if it's non-chlorine shock (potassium monopersulfate) is acidic so would only help to keep the pH down. If you use bleach, you'll then likely see even a greater rise in pH. The key is to get the TA lower, but you need a substitute pH buffer so that's why I suggested the borates.

If your Taylor kit says 5 ppm for bromine, then it's there and working. Some of it might be monobromamine and you may not like the smell of that, but it's still a disinfectant. Bromine isn't that sensitive to changes in pH in the pH range used in spas so I'm not sure what they mean by an "unbalanced spa". Your test kit is measuring total bromine regardless of the other water parameters.

Yes it is normal for shocking (i.e. adding any oxidizer to a bromine spa) to cause the bromine level to shoot up. That's what is supposed to happen. You shouldn't need to shock very often if you maintain the spa properly. With a chlorine spa properly maintained, you may never need to shock, but with bromine sometimes there are some organics that bromine doesn't handle as well as chlorine (shocking with MPS is a mixed bag -- it can oxidize some things better than bromine, but other things not as well as chlorine).