You may have already tackled this problem but in case you have not, and for the benefit of others, I share the following:
As far as solar covers, the typical one here in the states is sold by companies such as Leslie Pools.
Leslie Pool Solar Covers: http://www.lesliespool.com/Home/Pool-Covers/Solar-Covers.html
I strongly recommend the light blue style with a flat surface on the top and bubbles on the bottom. The light blue color is more effective because it allows light to travel deeper into the water.
Initially, I had only two solar panels but they were located on the ground which I eventually figured out was a giant heat sink, robbing the solar panels of the solar heating. I solved this by elevating the solar panels and installing a check valve, vapor pressure valve and pressure gauge to monitor output into the pool. I also installed a gas fired heater but do not need it yet because the solar panels are delivering a constant 85-88˚F after a day of solar heating in conjunction with use of the solar blanket. I am very happy with my design.