Higher chlorine loss than last year

[brent.roberts]

Question: when is the last time you cleaned out your filter.

Maybe there is a lot of junk in there that you can't see that is consuming some
of the chlorine.

Put a cover on to stop the sunlight loss. You're going to burn up the cost of a cover in extra chlorine. Even in NJ the sun is very high this time of year and the UV loss can be huge.

[dancu]

Oh, I like that idea!
Pool is 3 years old, sand filter never never got cleaned or replaced only backwashed
Drop in cl overnight while at shock levels with the filter running all night was minimal though...
Just thought about the light niches,what or the odds something is growing in there, or am I losing it now......

[brent.roberts]

If you got no significant drop in chlorine overnight, then I don't think gunk in the filter is the issue. From what I have seen in weather patterns most of NE USA and our area in Canada (Toronto) has had much greater than normal amounts of sunlight. We only got 1/4" of rain in June and normally get 2 1/2", so UV action on the chlorine will be much higher than normal. Maybe just carry on and see if it goes back to normal for you when we get more normal weather.

By the way, despite what some pool stores tell you, filter sand almost never needs replacing.

Good luck

[dancu]

Does high UV fluctuate daily or is it more seasonal?
I always thought it had a direct relation to cloud cover.
Today was cloudy, 9 ppm 6AM, 4 ppm 6 PM or do I need many cloudy days
for the effect of UV to drop?
Are there more factors related to UV strenght?

Dan

Buying stock in bleach factories

[chem geek]

Thicker clouds can block a lot of UV, but thin clouds may still pass 60-80 percent of the UV through (which is why you can still get sunburn even if you feel cool because thin clouds reflect most of the infrared heat). The UV is also directly related to the total radiation from the sun which changes by time of day and time of year, both relating to the angle of incidence of the sun relative to vertical. There is a direct angle effect (based on the cosine of the angle if vertical is 0 degrees) plus at lower angles there is an additional effect from the extra absorption by the sunlight passing through more of the atmosphere.

This link will let you see the amount of solar radiation in your part of the country at different times of year. HOWEVER, this is an average over day and night and includes the actual cloud cover. Even the "maximum" is for the month average, not a peak during the day with no clouds. You can see that the east coast and even Florida has lots of daily clouds that lower potential output compared to the southwest.

There was a link on the web to a calculator that would tell you the peak solar radiation at any time of year and time of day for a given latitude, but I can't seem to find that.

Richard

[dancu]

Just wanted to post some conclusions.
Never was able to lower the chlorine consumption this season.
Pool stayed cristal clear only if kept above 6 ppm, cya is 40 now
No chlorine loss overnight!
Loss per day is still 2ppm which is more than double compared with last year around this time.
I figure there is something else in the water that makes the cya ineffective.
Maybe antifreeze from last winter?
Any thoughts?
Also I am using Walmarts Ultra, which to me has a scent to it?

Thanks
Dan

[CarlD]

If you smell anything other than bleach, like a perfume, don't use it. Period.

One thing people forget is that each summer is different. One summer may be relatively bug (as in biters) free, the next may be mosquito-central. There's different levels of pollen, and other contaminants. It depends on the amounts of rain in the spring and summer and the amount of sunlight.

Saying that, this summer seems to have been one where there was a lot more biological stuff getting in the pools. My usual vacation ritual of having someone dump 1 gal of bleach in the pool every other day failed, and I came home to a mild algae infestation--for the first time. My system always worked in the past. So why did it fail? I don't know, but I just think there was more stuff to metabolize.

I don't know if this is right or wrong but it seems to fit the facts.