I just tested my water when I got home from work which I do almost everyday. I was wondering if it is better to test in the morning before the sun has hit or in the evening so you know how much bleach to add. Testing in the morning could give you more consistent numbers for the past 12 hours with no effect from the Sun but testing in the evening gives you a better idea of how much bleach you need to add to get your numbers right. I may be overthinking it as my numbers are in a pretty good rhythm but I was just curious.
Daily water test in evening or morning?
- Thread starter AndyTN
- Start date
- Jun 22, 2014
- 47,789
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
I see it done either way depending on one's schedule at home. You could argue either way I suppose, but I don't think it really matters as long as you are consistent so that you can monitor your pool's pattern of chemical changes - especially FC.
Oly
Gold Supporter
The time of your test will tell you different things. Testing a couple hours after an application will confirm your application effect and your estimations like pool volume.
Testing again in the early morning after a sundown chlorine application and confirmation test will provide you an Overnight Chlorine Loss value which details FC loss not associated with solar radiation and isolates organics.
Waiting 20+ hours after an application will give you an idea of your daily FC loss. This number will change with the seasons.
Testing again in the early morning after a sundown chlorine application and confirmation test will provide you an Overnight Chlorine Loss value which details FC loss not associated with solar radiation and isolates organics.
Waiting 20+ hours after an application will give you an idea of your daily FC loss. This number will change with the seasons.
- Jul 21, 2013
- 52,426
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
There should be little to no FC loss between sundown and daylight on your pool. So the evening FC reading or early morning FC should be about the same.
As Splash said, do it the same time if you can.
As Splash said, do it the same time if you can.
I think evening is better, if your adding chlorine it has the night to work, before the sun hits it and burns it off.... About once I week, I would say, test both, evening and morning, to see if there is any loss over night, that could indicate problems.
lindz18
0
Are you leaving pool running at night when you add in eve or just adding letting it mix, then turning off?
I test daily in the 12-2 PM window.
I think it is more important to do a repeat time daily then what time you do the tests.
I think it is more important to do a repeat time daily then what time you do the tests.
I will normally test and add chemicals around 6 when I get home from work and turn it off around 8-8:30 before going to bed. This time of year, I am usually leaving it on 24/7 so the fountain can run to cool down the water but that is only for 2 months out of the year.
RJPRESTRIDGE
Member
I test/dose the pool in the evening, let the water mix for 30 minutes and turn the pump off. Full FC level at night should give any algae a kick to the head, before the sun's UV comes into play.
Wobblerlorri
Bronze Supporter
- Apr 16, 2019
- 2,010
- Pool Size
- 4024
- Surface
- Vinyl
- Chlorine
- Liquid Chlorine
I test and dose in the evening as well. My pump generally runs from 3 p.m. to 7 p.m., and I test around 5:30 p.m. or so. The sun is off the pool by then, and I can add chlorine without losing it to the sun. Has around 2 hours to mix.