I am looking to do a DIY install of solar heating panels for my IG pool. We have an existing wooden pergola that has a metal roof with very little pitch. I don't have the exact pitch, but think of it as a few inches or just enough to keep the water flowing off the metal roof. I know the structure itself is strong enough to hold the panels containing water, and it would be much preferred to install them there for two reasons. One, they would be almost unseen, and two, I know this is not truly an issue but it would in fact keep me from putting holes in a perfectly good, new roof.
Are certain panels or brands better for this kind of application? Thanks!