I have been kind of reading along and based on my "guesstimate" 7 4*12 panels are going to give you a lot of heat energy, which will be great when you have cold spells but overwhelming in the summer....unless you want the pool ti be giant hot tub!

I use the equivalent of 3 4*20 panels on a nearly 20k pool up on NJ and there are summer days where the water can reach into the high 90's! Then i run the solar system at night to radiate heat instead and cool the pool.

Remember that the faster the water flows through your panels, the more heat energy will transfer to your water. The limiting factors are how much pressure the panels can accept safely and how much pressure to them your pump can generate.