Worth putting 2 covers on?

[YonnyPiscinas]

Currently I have this excellent semi-rigid cover. Rolls back in 2-3 mins.

Now I have my solar panels on a lot and am trying to maintain the temp above 31c!

We are in summer here and get daytime temperatures anywhere between 20 and 35+.
But at night can drop to 16c often with a lot of cool wind. (update 14c last night!)
I can get 2-4c gain each day but will lose at least 1-2c each night on the cooler nights.

I'm thinking of adding another layer, the bubble wrap kind that floats on the surface.
Good thing about having the semi-rigid cover is that most of the dirt does not end up back in the pool. I can just jetwash it off ot brush the heavier debris off. Some smaller particles get in through the air vents (2.5cm in diameter) during heavy rainfall.

Bit of a pain removing both but if it going to make a big difference in night time loss may be worth it.
Should only cost about 100-120 USD.

Are the bubble wrap types much better at insulating the water?

I see 300-600 micron types. Thinking of the thinner one for ease of removal considering it's a second cover

(Graden is a bit messy sorry - in the middle of renovations!)

 

[Bama Rambler]

I'm not sure that the 'solar' covers are much better insulation than your current cover, but it may be worth a try. Especially if wind is getting under your existing cover. A cover that lays right on the water surface will hold more heat than one that hangs a few cm above it.

If I were going to try one I'd get as thick a one as I could find, as the trapped air is what does the insulating. And cut it to lay evenly on the water surface.

 

[YonnyPiscinas]

I'm not sure that the 'solar' covers are much better insulation than your current cover, but it may be worth a try. Especially if wind is getting under your existing cover. A cover that lays right on the water surface will hold more heat than one that hangs a few cm above it.

If I were going to try one I'd get as thick a one as I could find, as the trapped air is what does the insulating. And cut it to lay evenly on the water surface.

There is a good 15-20cm between the water level and cover at the moment. When you remove it you get hit with a wave of hot air.
I'm very tempted to buy a bubble cover next week.

Seal is good with the current one but yes it has the small air vents and probably is not that efficient at keeping heat. It has stopped all evaporation from the wind though.
Very safe option also as you can walk on it. Safe for my son and our dog.

 

[Newdude]

I can testify that using a solar cover helped my hot tub alot. It’s a smaller scale but almost identical otherwise with a small air gap under the insulated cover.

 

[YonnyPiscinas]

Bit like double glazing!

 

[YonnyPiscinas]

My mind is made up. I'll look at prices over the weekend. Shouldn't be more than 100-120 bucks as its a small pool, so easier to roll back also.
Wife said it would be a pain removing but she is the first to complain when it doesn't feel like a hot tub!! (and always asking me throughout the day how hot is the pool! That's why a put a digital thermometer in the pool this week to read it from my phone.)

Double glazing on the pool surface and more panels!! (Or just move to Miami!)

 

[sktn77a]

Cut it into at least 2 pieces to make handling easier. For ~$100, it's worth trying.

 

[YonnyPiscinas]

Thanks. Yes I'll but 2 strips of 1.5m x 5m. Works out cheaper too with the 1.5m roll!

Another thought. I have a lot of small vent holes in the cover with a mesh.
I find during rainstorms a lot of the fine debris gets washed in. Also you can feel the heat escaping on a cold night through the vents.
I was thinking of sealing some up, possibly the 2 inner rows. Does it really need all those air vents?

 

[YonnyPiscinas]

hmm bit disappointed to be honest now. Had the new 12mil cover on for 3 nights now with the semi-rigid over.
Thought I would halve the temperature drop with 2 covers on.

Still lose 2c overnight. Maybe heat transfer through the sides and bottom of the fiberglass pool also.
May help on the colder nights but at the moment not really cost effective (120 USD).

Pool gets up to 36c end of the day. 34c in the morning.
Mind you with a night temperature of 16-20c this is a big difference (dropped to 12c earlier this week!!). Put your hand over the skimmer vent and you can feel the hot vapor coming out.