Just starting to cool off here in Florida and trying to figure out how to extend my swimming season. Our neighbors got a big piece of small-sized bubble wrap that seems to work pretty well for their small kidney pool, about 1/2 the size of ours, and they are chlorine. I don't think their bubble wrap cover is anything special for a pool but it lasted two seasons (haven't seen it yet this year, but their pool is so messed up they haven't been swimming at all - they walk over and use ours!)

We are salt and have a spillover spa with two skimmers (the diagonal swim lane is measured 39' long)

(trying to paste a picture of the sketch here, but can't figure out how to do it with the new Google Picasa format - you'll have to click the link below to my blog to see the shape and size of the pool)

So I was thinking about getting two sections, roughly one for each leg of the pool, and a third section for the spa.

Do I need to cut out a space for the spillover? (If I don't, will it sink my cover?)

Also, any idea how much space a cover like this takes up when it's rolled or folded? If I got a 15mil clear cover, would it fit into a big Rubbermaid container or would I need to buy an extra shed?

I was thinking that a reflecting bottom would work like a space blanket and reflect the heat back into the pool, but I think that only works on people because we generate heat, and the pool doesn't. My engineering husband says the ideal cover would be clear on top, with as much air space for insulation as possible, and then dark bottom layer for conducting heat directly to the water. Now I'm reading that clear is better for radiant heating of the entire water column, while the conduction would only work for the first few inches of water? This is Florida, where we will have sun all winter, although at a shallow angle.

Any advice, words of wisdom, recommendations?

Here is a link that might be useful: Pool Blog with Sketch