When to open? Go by low daily temp or what?

This will be my first year for opening a pool. Have a 24 ft AG pool.

I'm in Iowa so swim season will probably start late May. But today temps were in the upper 70's. Is there some guideline as far as when a person needs to open in order to avoid algae?

Temp still drops at night. As long as its still dropping should things stay okay?
Like as long as it doesn't stay above 60 degrees 24 hrs a day?

I haven't peeked under the cover since closing it last fall.

I don't have decking around the pool yet so the only way I could vacuum last year was by being in the pool. I'm 5' 4" and pool has 52" walls. Sooooo, I'd hate to open early when the water is way too cold to get in it.

Thanks,
Lori

As long as you are getting temps below freezing at night, wait to open. When you are staying above that and having warm days, just keep an eye on your water. We kind of thought around here that as long as your water temp was below 50 degrees, you didn't really have to worry about any algae. Al (Poconos) and I both found out this winter that isn't necessarily true. We both had a slight streak or two of algae and both of us had temps below that. A quick shot of bleach took care of it. I understand your reason for not wanting to open only to have to keep cleaning a pool that you can't swim in. There really isn't a hard and fast answer as to when to open. Go ahead and reach under the cover and pull out a sample and test. As long as you are maintaining a chlorine reading, you should be OK for a bit.
Good luck.

Watermom

I don't cover my pool anymore and when the ice melts I just keep an eye on the water. Watermom was right in that I did have a slight algae bloom when the water was a little above 40 I believe. As for equipment, I wait until the temps won't hit the freezing damage point before hooking things up. Solar stuff won't get water until I'm REALLY sure they won't freeze. Be aware that on clear cool nights the solar heaters will become good radiators of heat and freeze first. With a clear sky they are looking at cold space. Before you fire up the equipment, if you have an algae problem, you can add chlorine (bleach or whatever) and circulate by any means, even a simple submersible cheapo pump.
Al

When I get sick of looking at by attractive but boring loop-loc cover...

Thanks for the input. I'll try to get the cover back a bit and check the water tomorrow. Hope I don't see any surprises in there. It was in the 80's yesterday and going to get below freezing again tonight. Gotta love Iowa weather. ;)

We also had 80s yesterday and below freezing (29 degrees) expected tonight. My pool is uncovered. Was covered in the fall, but my two golden retrievers chewed through the vinyl cord tying the cover down and it fell into the pool back in October. Dumped a lot of leaves and green water off the cover into the water. Shocked the heck out of my pool and decided not to bother with trying to put the cover back on since most of the leaves had already fallen from the trees by that point. Since my pool is uncovered and we are getting lots of warm days, went ahead and hooked up the pump/filter last weekend. Otherwise, I would have been risking an algae bloom. Anxious for the pool to get warm enough to swim - but we are a ways off from that. Current water temps are probably in the low 60s.

Here are a few pics of my pool after the cover fell in and a day later after the miracle cure (bleach!) was added. Gotta love that stuff! The dark spot you see in the middle of the second picture is a big pile of leaves that I had not yet scooped out. At that point, I was just concerned with getting rid of the green. Scooping the leaves out was taken care of a few days later. What a pain that was!

Watermom

Ick to the cover coming off but amazing what a little bleach can do.

I just got the cover back enough to get a sample. Water is clear but Cl is almost nonexistant.

FC - .5
CC - 1
TA - 70ish
CYA - none?
pH - 7.6 - 7.8

I've got to pump LOTS of water off my cover. Then I'll try to get it back enough to add 2 gallons of 5.25% bleach (no clue how many gallons since its drained down below skimmer but maybe about 10,000?). Also add some stablizer. pH should be okay for now I think.

My first year opening too- tonight is our coldest night for the next week- getting into the mid 30's. The next week calls for highs in the 70's with lows in 40's to 50's. What it's going to do after that, only God knows. We went from warm days to a blizzard and over 20 inches of snow on the first day of spring this year.

I'll also check my water tomorrow. I only had to pump water off my cover once this winter- just after our last big snow with rains following it, so mine is almost all off. Left some on it to help with the wind.

Mine is drained down too- and when I fill it- I'll have to treat it for iron again, so will need my filter/pump up and running.

I think I read that as long as you leave your pump/filter running - even if it gets colder at night it'll be ok- am I correct on this?? How cold is "colder"??

Last question- CarlD posted an answer on the lost forum, so I know he knows: how warm does your water have to be to put in and run an AquaBot Pool Rover Plus?? I also won't be climbing in cleaning anytime soon, lol! But with my solar panels (which I'll bypass until I'm positive it'll stay warm) I'm hoping to be swimming early May- depending on the weather of course. Can only dream anyway!

huskerfan,

When your pump is running, the temperature of the water running through the pump is more important than the temperature of the surrounding air.

My pool was built late last year and by the time I was able to close it I had survived several nights that got down into the 20s and even the teens once or twice.

Something else to consider about freezing temps. The filter gauge. Typically this is exposed to cold air, sticking out the side of the filter valve assembly, and is likely to freeze first as there is no real circulation through it. Once it freezes it's shot....but cheaply replaced. You can remove it and put in a pipe plug, or, as I do, wrap layers of old bedsheets, heavy cloth, or whatever over the top of the filter and valve assembly to utilize the mass of the filter to keep components from freezing. It takes both time and temperature to cause a freezing event that leads to damage.
Al