It might be best to wait till you have the kit, and can test systematically, before deciding what your pool's normal pH trend is.

Plus, there are several facts you need to consider:

+ It's not really possible to maintain BOTH a 'normal' pH AND 'normal' carbonate alkalinity levels, on a jetted spa or pool. The reason is that, at pH levels in the 'normal' range (7.2 - 7.8) aeration will ALWAYS strip carbonate alkalinity, until the pH goes up above 8.0.

+ Depending on the volume of AIR flow, a UV ozonator will tend to provide a CONSTANT source of aeration on your pool.

I'm actually discussing this issue with some of the moderators and contributors, and how we should respond. Historically, I've tended to encourage folks with spas to go elsewhere. For one thing, I personally don't like spas. But, more importantly, I don't have 'SpaSolutions" that parallel my 'PoolSolutions'.

One problem is the whole pH / can't maintain carbonate alkalinity just mentioned.

The other is, that stand-alone spas tend to be cess-pools. You can take care of a pool pretty easily with once-per-day attention. But the methods that work with a pool will not work with a spa, because the people to water ratio, and thus, people goo to total residual chlorine ratio, is so much worse on spa.

It's possible that the ozone system is a good idea for you, precisely because it will NOT create a sanitizer residual. Constant ozone feed will not create high levels of ozone, like constant chlorine feed would do.

But, I really don't have a good answer on the pH.

I can't tell you to forget about the alkalinity -- which I would do if you had anything OTHER than a concrete pool & spa -- because super low alkalinity may well result in plaster damage. But, there's simply no way to maintain 'normal' pH and at the same time 'normal' carbonate alkalinity, on a highly aerated pool & spa.

Here's what I suggest:
1. Get the K2006, and let's get a couple of weeks of chlorine + pH + TA readings under your belt. You'll also need CYA and calcium readings, but those don't need to be repeated. (There are only 6 CYA tests in the kit -- so don't waste them!)

2. Let me pursue this discussion with Chem_Geek and others, and see what we come up with.

3. Take a look at this page on PoolSolutions:
http://www.poolsolutions.com/gd/hiphpool.html
It's very relevant to your situation, as is this one:
http://www.poolsolutions.com/gd/lowe...p-by-step.html

4. Then, let's take a look. It may be best to run your pool & span with very low CA, low calcium and high pH.