Effect of whole house water filter on pool water

[RGS]

I have a question for ChemGeek or anyone with chemistry knowledge.

I have a whole-house water conditioning system, and the water to fill my pool comes through this system. A few months ago I drained and refilled the pool (to get rid of high CYA), and all the fill water also passed through this whole-house water filter. This filter is not a traditional water softener that exchanges calcium for sodium. It uses a technology called "Template Assisted Crystallization" (TAC), which does not remove calcium and magnesium ions but causes them to clump together so as to reduce scale formation. Here is a link to the website describing the technology:
http://water4systems.com/salt-free-water-conditioning.html
The filter also includes other stages for removing metals and other impurities as described here:
http://water4systems.com/scalestopfiltermax-how-it-works.html

My question is whether this filter should affect my pool calcium hardness testing results, or the desirable calcium levels in my pool?

Today I did a test of my city water (using my Taylor pool testing kit) before and after it goes through my whole -house filter. Here are the results:
Test | Before filter | After filter
pH 7.0 7.4
TA 110 100
CH 170 120

Currently my pool water tests are as follows: FC=5.5, CC <0.5, pH=7.6, TA=100, CH=230, CYA=50.
I do not have a SWG, and I am using bleach and muriatic acid as my regular pool maintenance chemicals. I have not added any calcium products to the pool, except for one day when I added some calcium hypochlorite because I had run out of bleach.

I'm also wondering if my whole-house filter will tend to reduce scale formation in my pool, although I am trying to keep all the pool chemistry at the traditional proper values, and not relying on this filter to protect my pool.

 

[BuckeyeChris]

I asked about TAC two years ago as we were deciding what type of whole-house softener to get. There wasn't really anyone here at that time that was using a TAC system, certainly not as a pool fill. If the Calcium's behavior is different, as TAC proclaims, your CH readings may sitll be high, but scaling might not act as predicted by pool math.

It would also be interesting to get a quart of TAC water and pre-TAC water, run the CH test, and see if the TAC process affects the CH test at all.

 

[RGS]

It would also be interesting to get a quart of TAC water and pre-TAC water, run the CH test, and see if the TAC process affects the CH test at all.

A couple days ago I did a test of the pre-TAC and post-TAC water using my Taylor kit, with 25 ml samples, and the result was 170 pre-TAC, 120 post-TAC. I did the tests with water samples that were less than half an hour apart. I have one outdoor faucet that gets the water before the filter. So it does appear that TAC causes a lower reading on the CH test (unless somehow my filter is actually removing a percentage of the calcium).
My pool water currently shows 230, but it was refilled 3 months ago so there may have been some evaporation.

 

[RGS]

I found a reference for TAC that seems to answer my question. It said the following:
"TAC is a physical water treatment device. It does not soften water and it is not a “salt free” water softener. It does not change the hardness of the water. TAC converts dissolved temporary hardness ions into microscopic nano-crystals. This prevents the hardness in the water from sticking to the plumbing components as scale inside the plumbing system. ...After 2 days the water will re-dissolve the crystal back into solution and it is now able to form scale again. This is why TAC medias is not recommended for closed loop applications."
That tells me that most of the CH in my pool will exist in the normal form, as if I did not have TAC, so that I should just follow the regular guidelines regarding monitoring the CH levels in my pool (and calculating the LSI). I did not install the whole-house water filter for any reasons related to my pool, but I became curious about its possible effect on the pool chemistry, once I realized that all the fill water went through that filter.
Here is the reference I found on TAC:

http://www.owqa.org/TAC.pdf