I want to buy an above ground pool solar heating system that is simple to install and give me a few extra degrees of warmth when I need it...especially in the spring...Last Spring was first year with pool and we had a cool spring...I want to take that 70-72 degree temperature and kick it up to 78-80 degrees. Do these pool side solar systems such as the Solar Bear or Sungraber systems work well. The pool store says they do add about 10 degrees...But I don't buy everything they tell me...Anyone here use them? Do they add to your swiming season? If so how much...I have the perfect back yard for it...I get Sun from 9 am to 5 pm...Any help would be great.