Alkalinity is High?

[Drayden21]

I am new to trouble free pool. I have been a pool owner now for 4 years. trying to learn more about maintaining my pool rather than relying on someone else. I had my water tested today and I am suspect about the results. before I had it tested I use 6 test strips to test myself. my results seemed fine. FC, TC, and alk seemed a little high. the results from my local pool store: FC: 5.5 TC: 5.5 CC: 0.0
PH: 7.5 Hardness: 260ppm Alkalinity (w/stabilizer correction) 0ppm CYA: 75ppm.
cant understand why I have a 0 alk when I my test strip actually showed a little high.

I shocked the pool on monday. and havnt had any 3" tabs since tuesday being that the chlorine seems high. curious to know why my chlorine levels are high and I havnt had any chlorine tabs in since tuesday. I have had problems this year keeping my chlorine level up. the pool store said it is because of the phosphates in my pool.

19000 gallons
D.E. filter
plaster.
Pentair filter fnsp60 (I think?)

 

[JasonLion]

Welcome to TFP!

Alkalinity can't be zero when the PH is 7.5, that is simply not possible. Their test must be wrong.

 

[Voodoo_Pool]

Welcome to TFP!

Since you are questioning the results of the water test from your pool store, I would recommend getting a quality test kit so you can do your own testing. Please see: pool-school/pool_test_kit_comparison

Remember, shocking is a process not a product. Please see: pool-school/shocking_your_pool

Most of us shy away from tablets for various reasons. Please see: pool-school/types_chlorine_pool

Use this chart to determine your desired chlorine level based on your CYA: pool-school/chlorine_cya_chart_shock

I also recommend reading Pool School (button in top right corner of webpage) for even more great advice.

Of note, phosphates are not a concern in a properly sanitized pool. Save your money, should the pool store try to sell you something to rid your pool of phosphates.

Have fun, ask questions, and enjoy!