Opening and balancing questions

[Jcgage0]

I'm opening this weekend and I have a couple questions.

I added 5 lbs of stabilizer and two gallons of 10% bleach last night. My readings prior to this where.

FC=0,PH=7.4, TA=30, CYA=0

I ran the pump all night and I'm continuing this morning. The pump has been mixing in the chems for about 14 hours. The test this mourning showed.

FC=20.5, PH=7.4, TA=90, CYA=37, CC=0

A couple questions.

1. That is a lot more FC than I intended to add. Thoughts?
2. The TA went up 60 ppm without adding any baking soda. Does the high FC reading effect TA readings?
3. I read hear that the CYA may take a week to show up in tests (also that I should have added it a lot slower via sock in skimmer method. Whoops). I got 37 over 14 hours which is the right level but getting that reading in such a short period of time concerned me. Should I expect it to keep going up over the next week? That would be bad. Or is it just going to read sporadically over the next week and I should disregard the readings.

Thanks for the help and happy opening!

 

[karmabiker]

No need to fret over the FC ... it will come down.
usually 1 week for all of the CYA to show up ... at this point just monitor it. ...perfect argument for why to try to move CYA in increments.

2 possibilities for the Jump:
#1 You got some REALLY fresh bleach (possible - sometimes they start it at 15% so it will be at 10% when it gets to the consumer.)
#2 You are off on your pool size calculations.

Hope for #1 ... if its #2 the only option to correct the CYA (if it follows the CL pattern) is a partial drain and fill.

 

[JasonLion]

1) It is easy to be off by 20-30% due to things like varying bleach strength, measurement errors, etc, but your numbers are about double of what I would expect. You need to look around for errors in your assumptions. For example the pool might be smaller than you think it is (sloped sides in vinyl pools reduce their volume), you might have done the test incorrectly somehow, or the bleach is much stronger than you think it is (happens sometimes).

2) Again, that is a larger effect than I would expect or can easily account for. Adding CYA does raise the TA level a bit, typically by about 1/3 of the amount it raises the CYA level, so nowhere near what you observed. No easy explanation presents it's self other than perhaps testing error of some kind or other chemicals added that you didn't mention. One good double check is to do the TA test again two or three times and see if you get repeatable numbers.

3) The CYA level will almost certainly go up some more, though maybe by a lot, or maybe not all that much. The amount of time it takes CYA to dissolve varies. We say to wait a week because that is the longest it might take. It can be quite a bit faster on occasion. Still I very much doubt that it has all dissolved already.

 

[Jcgage0]

Follow up to the adding way to much CYA at once. I mixed it in a 5 gallon bucket with pool water and added it at the return. I just stared pulling the cover off and a large portion of my Stabilizer is sitting on the liner at the bottom of the pool. With the reading of 37 and so much of this stabilizer witting obviously unmixed on the bottom of the pool should I try and scoop it out or brush until it dissolves.

Will it damage the liner?

 

[karmabiker]

Personally ... I would try to scoop it out.

Plastic dust pan and a wet suit?

 

[JasonLion]

Yes, if CYA sits in one place too long it can damage the liner. You should never add CYA directly to the pool. We recommend the sock method, adding to the skimmer also works. But adding directly to the pool risks damaging the pool surface.

Are you getting test results from a pool store? Or testing yourself?

 

[timerguy]

I'm opening this weekend and I have a couple questions.

I added 5 lbs of stabilizer and two gallons of 10% bleach last night. My readings prior to this where.

FC=0,PH=7.4, TA=30, CYA=0

I ran the pump all night and I'm continuing this morning. The pump has been mixing in the chems for about 14 hours. The test this mourning showed.

FC=20.5, PH=7.4, TA=90, CYA=37, CC=0

A couple questions.

1. That is a lot more FC than I intended to add. Thoughts?
2. The TA went up 60 ppm without adding any baking soda. Does the high FC reading effect TA readings?
3. I read hear that the CYA may take a week to show up in tests (also that I should have added it a lot slower via sock in skimmer method. Whoops). I got 37 over 14 hours which is the right level but getting that reading in such a short period of time concerned me. Should I expect it to keep going up over the next week? That would be bad. Or is it just going to read sporadically over the next week and I should disregard the readings.

Thanks for the help and happy opening!

Adding 5 lbs "should" increase your cya by 30ppm even if it's 37, that won't hurt anything. But---- either your weight measurement is off a bit (way), or as karmabiker says you're pool size/ capacity is off.