My First Open

[acgibson]

Ok, I opened my pool for the first time yesterday. It was clear with only a few leaves, cypress needles, and about 20 crawdads scattered on bottom. There was no visible signs of algae.

Readings after I added water and pump ran for couple hours (7 P.M.)

6.8 FC (I added about 50oz in skimmer when I first fired up pump)
0.0 CC
7.5 pH
110 TA
270CH
25-30 CYA
30 Borate
3350 Salt (according to SWG)

water temp was 56 at open


OCLT 12hrs (7 A.M.) with cover on all night (SWG unplugged):

Water Temp 67

6.6 FC
0.0 CC
7.5 pH
110 TA
270 CH
25-30 CYA


So does this mean I made it through winter without issues in the Water (other than running jets to bring TA down a little)?

One thing I am wondering is why my CYA went down over the winter it was around 50-60 when closed? I know I added about 6" of water that would dilute it a little when I opened, but I didn't expect it to be cut in half. Does water temp or something consume it or mess with test? Pool Math called for 110 oz to get it to 70, but I only added 32oz in skimmer basket to start incase the readings were off and I checked here.

 

[JasonLion]

It is not uncommon to lose some CYA over the winter. If only we could get that to happen on purpose.

 

[acgibson]

Is the first day too soon to do a oclt? Is another one needed in a few days when water is warmer?

 

[JasonLion]

You are much more likely to fail an OCLT the first night, but having passed you should be fine.

 

[acgibson]

I only lost another 0.2 FC in 24hrs with no chlorine additions (cover was on entire time). All other readings stayed same.

Thanks Jason

 

[Patrick_B]

Hey AC,

May I suggest using a 10ml sample size for FC? Entirely up to you, but it will save you some Titrating reagent.

 

[acgibson]

Thanks Patrick, yeah I usually do but for the opening and OCLT'S I used the 25mL for the accuracy.