Solar operated fountain, sounds good, no running costs, what more can you ask for? If it were only that simple. If you have a quick search for "solar fountain" you will find lots of them....................all designed to go in a back garden tiny pond. I say tiny pond because at best the jet height is less than a foot (and that is if you are lucky) With a pool as big as yours you are going to need a jet(s) that are in the region of 5 foot tall, anything smaller and you will not be able to see it. The down side is there is not readily available a 12v pump (it is solar) that can do that, and if there were it would need an array of solar panels to generate enough electricity. There is also the consideration of where would you mount the solar panels? (Not to mention the cost of the solar panels)
You may want to read an article I wrote some time ago, its still as true now as it was then, Click Here
You would be far better off with a mains operated fountain, since it can have lights and run when ever you want it to.
If you do have any other questions, please reply here.
The article I linked to was written by me 10 years ago, so I thought it best I double check.
The price of (small) solar fountains has come way down, average price is now £10 but is really designed for a bird bath or tiny pond. (Which is what I said 10 years ago)
I was able to find a large solar floating fountain (See picture) which is suitable for the OP. However as I said 10 years ago, any such fountain will need an array of solar panels and will not be cheap, I was correct on both counts, this one needs 4 solar panels mounted on a pole (Pole not supplied) although I suspect as the fountain is in America it will probably need 6 or 8 solar panels to make it work over here, there will also be shipping to add to the cost as well as import duty and V.A.T. (The seller also said the price is subject to sales tax, thats an American thing) oh and the cost before you add on all the shipping, vat, duty etc? $6,900 roughly £5,300 Still want solar? I thought not.