I use the 8g nano version for my crs, which is the same as 4g nano just larger and the led light will grow low-med plant. However i did remove the back though. I hate the sump area in the back, it doesn't work like intended.
This was one of my concerns. Can you elaborate at all on the issues with it?
So you ended up with just a glass tank and light and using some other filtration method instead?