Hello all!

I'm looking to install solar heat for our pool this year. I've come across some guardian panels in 4x12' size for a decent price. I have 7 of them, but I'm unsure if I have the roof space.

Pic of the house, straight up is North



The front of the house gets shade from the trees (and faces south), the west side of the house will have shade in the afternoon in 4-5 years from bamboo that has been planted. The white roof is a very slight grade, maybe 10%. It gets sun nearly all day year round (Pic is winter mid/day....2nd story shade is pictured).

Pool equipment is depicted on the first picture.

Here is a picture of the patio roof with a panel laid out on it. Obviously I would need to pull it onto the roof slightly higher.






Questions:

Is the slight angle enough for drainback when the system isn't circulating?
Is the angle in the panels going to cause issues with longevity?

What else could I do that I'm not thinking of. I don't have a ton tied up in the panels I have now ($450) but I'd like to use what I have.