no expert but i'll challenge that blue vs clear solar cover notion

[tenax]

notion i'm referring to is that a blue or opaque cover will not transfer heat to a pool, but only retain heat. i was buying that idea until today when i added a thermometer. my pool was covered overnight and this morning until about 11am at which point we had a 1 hour or so swim..then i put the cover back on (blue solar cover with the bubbles).before, during and after , the pool was a steady 85 farenheit. it's 4:30pm out now, definitely air temperature is warmer than when we went swimming this morning and the pool temperature down to the same level i checked before anyway (18 inches) is now 88 farenheit. and the cover aside from about 1 inches all around is completely on..so, either that 1 inches of exposed water is absorbing that much heat..or the blue cover does conduct some heat to the water, rather than just heat retention. now, i'm not suggesting it would conduct heat as well as a clear,but nevertheless, my logic says it does conduct some versus heat retention only.

to further back up that theory, if a blue cover didn't conduct heat, why would we bother covering it up when not in the pool? if that is necessary, that tells me that the water acts as a heat sink for the heat from a cover sitting in the sun to absorb heat.

finally..and most importantly, cause the above is all just fun learning stuff and thinking for me, no question the cover works..and well. i normally run my heater in our climate about 6 hours per day to keep it at 85 farenheit. i ran the heater only about 3 hours yesterday morning, then 2 hours this morning..maybe (i think may have been only an hour!) and the pool is staying nice and warm..great investment!

[CarlD]

You misunderstood me: A clear cover passes more sunlight, allowing the pool to heat more. That's all.

[tenax]

hope you didn't take it personally carl..more than one person here has claimed that a blue solar cover does not absorb heat but only contains it from the water..(and not saying that's what you in particular said)

yes, i do know how to stay on the good side of a supermod

thanks carl!

[CarlD]

A solar cover can heat your water by:
Getting hot and conduction of heat to the water.
Acting like a greenhouse and preventing heat from leaving (insulation)
Acting like a greenhouse and allowing sunlight to pass through and heat the water directly.

A clear cover does all three, but the first it does least effectively.

An opaque cover does the first two, but not the third.

A transparent blue cover does all three, the first slightly more effectively than a clear cover, but the third seems to be less effective than a clear cover.

I've had all three and prefer a clear cover, heavy enough to give good insulation.

[tenax]

very good explanation Carl..(and that's not a suck up) thanks a bunch for clarifying.