First post, new pool, first test results. Looking for advice.

[briand_69]

Hello,

Just finished setting up an Intex 18x9x52 pool and filled it 3 days ago. Everything should show in my sig I hope!

Anyways, received my Tf100 test kit yesterday. I added salt the first day (2 40# bags) and ran the filter 24 hours before turning on the SWG. 24 hours later I added the CYA (.7 lbs via digital scale) using the sock over the return jet method. Here are my results so far. I think I'm ok but the CYA doesn't show yet, but its only been 24 hours, but the TA is a bit high.

Water temp 79-80 deg F
Salt test- 2800 ppm (drop method)
PH- 7.6
TA- 140-150
CYA- Less than 20, dot disappears when vial is almost full
FC 4.5 with the accurate test, over 5 but below 10 with the daily test
CC. .5 or less Water goes clear instantly without swirling if that matters.

Should I make moves for TA or wait? It's supposed to be very hot today so kids want to use the pool, but the next several days it will probably not be used. Water is crystal clear.

Thanks
Brian

 

[atttech-2]

Looks good, I would leave the TA alone the SWG and kids splashing around will bring it down. You may end up using a bit more acid till it comes down but should not be a big problem.

 

[Texas Splash]

Hello Brian and welcome to TFP! You seem to be on-track. Keep an eye on that CYA. Once the stabilizer fully dissolves from the sock, it shouldn't take more than a couples days to register. Say, is that pool size correct in your sig (18' x 9' x 52" deep (4'3")? I'm only coming-up with 5,200 gallons on the Poolmath Calculator. I must be off somewhere.

 

[briand_69]

Yes, that is correct. In the filter book that came with the pool it says water capacity is 4,545 gallons which is calculated at 90%. And I'm about 3" below the full line with the skimmer attached.

Brian

 

[Texas Splash]

The reason I ask Brian is I was comparing the amount of stabilizer required. Since you have a SWG pool, I'm assuming you want to get to the TFP minimum of 70 correct? If I used 5K as a general pool volume, then the calculator tells me to go from a CYA of zero to 70 is requires 47 ounces (2 lbs 15 ounces) of granular stabilizer. To go only to the non-SWG minimum CYA of 30, it would be 20 ounces (1lb 4 ounces). You mentioned a digital scale to measure, but I just wanted to make sure you added the right amount.

 

[briand_69]

Think I should add more now or what another day and retest? I went a little low knowing the pool isn't full and I didn't want to overshoot it. If my math is correct the pool should be right around 4,300 gallons based on not being full.

 

[Texas Splash]

I adjusted my calculator to 4,300 gallons. So 1 lb will get you real close to a CYA of 30. You can give it a day or so to see how your first estimate worked-out. Once you evaluate that first batch, you can take a leap towards adding a second dose to get you closer to the SWG-recommend 70-80 range - probably about another 24 ounces.

 

[atttech-2]

You are approaching it the right way increase a bit at a time to get where you want to be.

The problems with high CYA usually has more to do with 1.) people not knowing the FC to CYA relationship so they keep FC at 3ppm with a CYA of say 100 and end up with algae and 2.) For those who do understand but still have high CYA having to use large amounts of chlorine to slam if they get a bloom. You are somewhat lucky not only do you appear to understand and there fore will not end up with high CYA but even if you did over shoot your pool has a small enough volume you could have a CYA of 100 and still successfully slam with a relative small amount of chlorine.

 

[briand_69]

So after the pool was used yesterday, I did a quick vacuum and added salt and CYA using the pool math. Ran the SWG 8 hours and the filter is still running. Before adding anything I checked CL using the daily test and it was almost gone, maybe a 1 or 2. Tested everything this morning and here's my results, TA still the same

Water temp 78
PH- 7.5
TA- 150
Salt PPM 3200
CYA 45
Calcium 120
FC- 4.5
CC-0

So, other than the TA everything looks great I think. Pool is crystal clear still. The pool won't be used for the next several days at least since it has cooled off a lot so all I'll be doing is watching it. Should I try and move the TA at this point?

Added edit- Tested the fill water and the TA is 130 if that matters.

Thanks

Brian

 

[Texas Splash]

Good to hear Brian. As for the TA, the only reason you really need to adjust TA is if it is effecting your pH (making pH rise). Aeration (swimming, SWG, fountains, etc) make pH rise, but a high TA could also cause pH increase much faster. So if you feel over time that the pH rises just too fast, then use the acid/aeration method to lower TA as note on the Pool School - Lower Total Alkalinity page.