I am creating a solar heater for my Intex 3000 gallon above ground pool in which the water will be routed through 1000' of irrigation tubing (0.6" inside diameter).  My challenge is that I have a nearly 100% shaded yard and the only place with any measure of sun is on the roof of my 2nd story house (and even that is only 4-5 hours).  The water therefore needs to overcome the friction of 1000' of tubing and reach a maximum height of 23'.  

So what pump do people think I need for this application?  Does it matter that the water will be routed down from the roof and back into the pool, thereby creating a suction effect?

Any help you could provide would be great.  Thank you.