Chemistry is spot on, but water is cloudy...

wes8398 · Jun 23, 2011

Maybe it's just coincidence that the water has gone cloudy after I've had a new solar cover on the pool for the past 5 days, but I thought I should mention that. Its just one of those blue bubble covers, 15 mil thick.
Todays test results:
Temp - 74*
FC - 2.5
CC - 0
pH - 7.2
TA - 110
CH - 230
CYA - 30 (I know it's low-ish, but it's been working fine with same daily FC loss as last year when I had CYA of 80)

What could be causing the cloudy water? I haven't had ANY algae problems this year or last year, FC has never been close to 0 or even under 2ppm (test nightly) so I can't see how the particles in the water could be algae (dead or otherwise). One other thing I should mention is that I have the pump on a timer which runs the pool for three 2.5 hour intervals each day.
After realizing the water was cloudy and testing tonight, I added half a box of Borax (just because) and about 7 liters of 12.5% chlorine. I haven't "shocked" the pool since I opened it over a month ago, so I thought now was as good a time as any.

Any ideas? Comments?

JohnT · Jun 23, 2011

One possibility would be localized chlorine drop during the off time allowing algae to get started. I'd always advise increasing pump run time when a problem arises. It accomplishes both better chemical mixing and better filtering.

Butterfly · Jun 23, 2011

I'd shock it, too. :goodjob:

Maybe that new cover had something on it that contaminated the water?

You may not learn for sure what caused it, but you know how to fix it!

wes8398 · Jun 23, 2011

JohnT said:
One possibility would be localized chlorine drop during the off time allowing algae to get started. I'd always advise increasing pump run time when a problem arises. It accomplishes both better chemical mixing and better filtering.

I almost always add my chlorine while the pump is running and will continue running for at least another half hour or so. I would think that this would ensure that the chlorine gets dispersed throughout the pool.

I took a look at it tonight with the 2 submersed lights on ... Looks pretty bad man. I can't see the main drain which is only 8 feet down because of the cloudiness. I set the pump/filter to run continuously from about 7 this evening and through the night. I'll have a look in the morning before work and see how it's looking; Hopefully improved!

wes8398 · Jun 24, 2011

It looked better this morning. Still cloudy, but I can almost make out the main drain now. I only had time to test chlorine and pH. FC was about 12, CC was .5 (a lot of rain overnight), and pH looked to be much higher at 7.6ish. Im assuming the rise in pH is because of the high chlorine.

Like I said, still pretty cloudy though. I increased pump run time to three 3 hour intervals rather than 2.5 hour intervals...

frustratedpoolmom · Jun 24, 2011

run it nonstop till the cloudiness goes away and then work on increasing the runtime till you find the ideal setting.

Always run the pump 24/7 when shocking.

JohnT · Jun 24, 2011

wes8398 said:
I almost always add my chlorine while the pump is running and will continue running for at least another half hour or so. I would think that this would ensure that the chlorine gets dispersed throughout the pool.

What I mean is that during the periods of no circulation, something may be consuming the chlorine in part of the pool allowing a little algae to get started. For example, if the sunlight depletes the chlorine from the top 6" of the water during the pump off time, you could see local 0 FC areas even though it will be back to 2ppm when the pump runs again. Running the pump more or choosing the time you run differently may give you better results.

I'd be nervous about running at 30ppm CYA. I don't think I could keep up with the chlorine in my pool there during sunny days.

jasonknox · Jun 24, 2011

My pool got cloudy as well last week. I just kept up my normal game plan for testing and adding chemicals and it cleared up. I don't know it the cloudiness came from me brushing (which I don't do often) or the church youth coming over to swim, but it finally went away. Since I got my new pool cleaner I have not brushed as I should. My pool never gets below 4ppm of chorine.

FC 5
CC 0
PH 7.5
TA 80
CYA 50
Borates 50

wes8398 · Jun 25, 2011

JohnT said:
wes8398 said:

I almost always add my chlorine while the pump is running and will continue running for at least another half hour or so. I would think that this would ensure that the chlorine gets dispersed throughout the pool.

Click to expand...

What I mean is that during the periods of no circulation, something may be consuming the chlorine in part of the pool allowing a little algae to get started. For example, if the sunlight depletes the chlorine from the top 6" of the water during the pump off time, you could see local 0 FC areas even though it will be back to 2ppm when the pump runs again. Running the pump more or choosing the time you run differently may give you better results.

I'd be nervous about running at 30ppm CYA. I don't think I could keep up with the chlorine in my pool there during sunny days.

I knew what you were trying to say. I didn't mean to come across as though I didn't. I'm just not sure I buy into this 'localized burn off' idea, that's all. But I do appreciate the suggestion.

As for the CYA, like I said, it's been holding just as well with 30ppm as it did last year with ~70ppm. No need to change something that's working fine, right?

As for the cloudiness, after running it through the night I put it back to it's modified 3 hour interval schedule for the day. Looked and tested it when i got home from work (12 hours after my previous post) and the water was clearer again and still holding about 9ppm TC which included .5 CC (from all the rain I'd guess).
I'm hoping that it's back to crystal clear when I get home tonight, so we'll see.