New pool owner, trying to get my chemicals balanced

[PoolDoc]

Interesting.

[mitchryan912]

Indeed it is, and they totally lost a sale by trying to sell me something else (over the phone.)

Oh well, my K-2006 is in the Chicago FedEx facility, and should be delivered by tomorrow at 8pm. It's perfect timing as I had to refill the pool (somehow lost a ton of water over the weekend) and will need to shock and adjust the pool this week to be ready for another big pool party this coming weekend.

[mitchryan912]

My K-2006 arrived today! I had to fill up the pool with the hose and had a rainstorm last night that added a bit of water. Interesting results from my first test:

7.4 pH
3.5 ppm TC
110 ppm TA
50 ppm CYA

I wasnt expecting these results at all, considering how much water was added after losing a lot over the weekend (~1000 gallons.) I last added acid, chlorine, & CYA about 8 days ago. My last test (7/3) at the pool store showed similar results, except for the CYA:

7.2 pH
5 ppm TC
110 ppm TA
15 ppm CYA

I backwashed a bit Saturday AM, and accidentally had something go wrong with putting the valve back to filter, and lost ~750 gallons. As such, I did NOT expect to see such a high CYA reading. Granted there could be some operator error involved, but I recently took a ton of college chemistry and biology classes (and had pretty good lab technique & grades), so I'm not sure if I did it grossly wrong. I will note that I'm taking the sample from the point of the pool where it starts to slope down to the deep end (the samples I had been taking to the store were all from the deep end.)

Just curious what to make of these and if I should shock the pool again this week?

[Watermom]

How does your water look? Why would you need to shock? You do need to add some chlorine so your chlorine levels don't drop below the minimum required based on your CYA ( http://pool9.net/cl-cya/) but not sure why you think you should shock.

[mitchryan912]

How does your water look?

Looks crystal clear, but there's a layer of stuff on the bottom of the pool that keeps coming back, as soon as a day or two after vacuuming. Some of it obviously is grass clippings and bits from the arbor vitae trees that line our property line, but the other stuff... I'm not sure if the stuff that tends to pile up along the liner seams is dirt clusters or not.

Why would you need to shock? You do need to add some chlorine so your chlorine levels don't drop below the minimum required based on your CYA ( http://pool9.net/cl-cya/) but not sure why you think you should shock.

I thought it was good form to shock after a heavy rain and/or every 10-14 days. Is the latter idea a pool store gimmick to increase chlorine sales? Either way, I think a goal of 3-5 sounds good to me since I'm not sure if my CYA level of 50 is correct. Is keeping it in this range as good as shocking it every so often?

For backwashing purposes, is it a big deal to have that much chlorine in the water that's being pumped into the street (and thus into the lakes)? My FIL said that it's best to backwash and rinse when the chlorine gets down to near zero so it doesn't kill the grass in the front of our property (the filter waste line goes from the backyard to the driveway, where it mostly goes into the street but some of it goes down the sidewalk.) I'm curious if that's good advice or not?

[Watermom]

As long as your chlorine never drops below your minimum per the CYA/Chlorine chart, you really don't ever have to shock the pool. Honestly, I seldom do. Of course the pool stores and pool chemical bags tell you to do it weekly to increase sales!

I have never had an issue with grass being killed from backwashing into my yard.

Regarding the stuff that keeps reappearing along the seam lines, it may very well just be dirt. I see the same thing in my pool. I vacuum very slowly and it appears to all be gone but then when the water quiets back down, it is inevitable that there will be a little dirt that had gotten into suspension that will resettle to the floor around the seams. Its no big deal. Much as we want to, it is impossible to keep an outdoor pool totally dirt-free.

[mitchryan912]

OK, that sounds good and is good to know about how clean to expect to see the bottom of the pool.

I'm using PoolCalc on my iPhone to figure out how much chems to add. It says that to raise FC from 3.5 to 5.0 in 26k of water, that I should add just a touch more than 1 quart of 12.5% chlorine. Granted I probably should have added it last night instead of now (tons of direct light on the pool in the early AM to about 3pm), but I hope to see it get close to 5ppm in the next hour to two.

Now that I have a K-2006, how often should be checking the levels? I'm assuming FC & pH should be daily, but how about CYA & TA? Should I ever need to bother with checking CH since I have a vinyl liner pool? Should I post these questions in the FAS-DPD forum?

[mitchryan912]

Regarding the stuff that keeps reappearing along the seam lines, it may very well just be dirt.

I discovered that it's actually mostly sand. I usually close my eyes underwater because the chlorine irritates my contacts, but used some goggles and got a close up view this evening. I wonder if that's coming from the filter?

[PoolDoc]

Strip based testing of CYA is HORRENDOUSLY inaccurate.

Watch the video of the Taylor CYA test if you want to validate your testing: http://pool9.net/tk/

[mitchryan912]

Strip based testing of CYA is HORRENDOUSLY inaccurate.

Watch the video of the Taylor CYA test if you want to validate your testing: http://pool9.net/tk/

I've tossed the strips and received a K-2006, so the reading of 50 ppm CYA is from my Taylor kit. It could be inaccurate, since it was my first time performing the test.