Ours is 27K so I don't qualify but that usually doesn't stop me. I am mostly satisfied without supplemental heat. Though bumping it up to 85, from our summer minimum of 80 would be very nice. We can get to the upper 80's and touch 90 during a hot stretch. However, I also have an autocover that, if we have a cool rainy few days in June, I will close it and that helps to retain a few degrees helping on the backside. You can see my Pool Math logs of our temps via the link in my signature or by clicking on my avatar and clicking Pool Math Logs. We have sun from about 8am to 7pm which is a huge help.