I'm sure that would work. On mine, I had problems with the full siphon or main drain pulling air from the surface with a loud sucking sound. So I just removed the standpipe completely and installed a strainer. Though, my overflow is diy glass instead of a reefsavy.
I'd suggest either making your main drain a little shorter, or you can add an additional pvc piece lowing the U further down. That would also be easy enough to do after it was finished too.
I'd suggest either making your main drain a little shorter, or you can add an additional pvc piece lowing the U further down. That would also be easy enough to do after it was finished too.