TA , CH and CYA results and CSI Calculations

[sharp7823]

Hello all. First post, but been lurking (and learning) for a while. Starting to get the hang of this and am going to have some questions along the way, but will start with a couple of few questions regarding my test from yesterday. Here are the results:

FC 6.4
CC 0.0
pH 7.5
TA 50
CH 250
CYA 50
Water Temp 58deg f
CSI -0.73 (Pool math) / 0.42 (Taylor watergram wheel)

So my CH was 180 and I added Calcium Chloride to get it up to 250. I will be adding more to get to it to 350-400ish. Is that a good plan?
Do I need to raise TA a little?
How about stabilizer should I add any?
Why are the pool math and Taylor CSI calculations different?
Our pool is 5 years old with a SWCG that runs from about April to October. In the winter months I drop a couple of tablets in the floater every so often and the FC stays pretty constant. Is there anything wrong with that approach? I know the TFP community likes LC over tablets.
Thank you!

 

[mknauss]

Welcome to the forum!
Have you tested your fill water CH? Most areas of California have elevated CH levels in their fill water. If yours is above 100 or so, I would not add any more calcium.
Stabilizer is fine for now. Depending on where you are in California, it can be raised to SWCG levels anywhere from early April to later in May.
Taylor does not use CSI. They use LSI, which ignores pool water chemistry. It is for steam boilers. Use Poolmath.
You can use tablets as long as you test. Rarely do tablets keep your FC in the target range based on the FC/CYA Levels
I suggest you read ABC's of Pool Water Chemistry.

 

[Texas Splash]

Welcome to TFP! In addition to Marty's comments, I would add:
- If you leave the CH at 250, let the pH rise to about 7.7 - 7.8. The cold water is making your CSI go low.
- Don't let the TA fall any lower than 50. A TA of 60-70 may be more ideal. It (and the pH) were probably pulled down from the acidic tablets.
Good post. Take care.

 

[sharp7823]

Thank you both!
I just tested tap water and CH is 60 and TA is 90.
Regarding the tablets, I should have clarified that I was keeping it in the 3ish range (I was good with anywhere from 2-4).
I will be adding salt in about a month as weather will be starting to warm up and I was shooting for the recommended levels in the TFP pool care basics.
Do you think a little baking soda is in order now, or should I wait a bit until the water warms up?

 

[mknauss]

Your fill water will add TA. Via evaporation.
If you like add a touch more calcium. Let pH ride near 8 and you are good.

 

[JamesW]

CSI -0.73 (Pool math) / 0.42 (Taylor watergram wheel)

For the wheel, you need to use "Adjusted TA" as described in the booklet that comes with the test kit and wheel.

 

[sharp7823]

Sounds like a plan, thanks! I shouldn't have too much trouble getting/keeping pH around 8 as it always seems to be around that level in the past.