Originally Posted by andresdeo
There is an inch and a half gap between the top rear of the tank and the back of the hood, to allow wiring and CO2
tubes to come out. Will post a photo when I get back home on sunday.
An inch and a half is not very much at all. Especially when there is CO2
involved. The degassing CO2
will fill the canopy due to lack of air flow causing a complete lack of air exchange. You will really need to keep an eye out on your fish for any potential issues. I would honestly look at adding a computer fan for more air flow if you don't want to cut the opening any larger.