Originally Posted by Aquaticz
Did Finnex say why?
They cited a potential for over heating due to a lack of airflow between the aquarium glass canopy and the ray2 splash shield, which isn't water proof.
I rest my ray2 fixtures on the glass canopy so I didn't want to bother with the "slide on" fixtures for clamping the light to the tank.
After contacting Finnex, I decided to slide them on to be safe.