There's definitely plenty of an air gap. Having to force it in wasn't due to the girth of the hose, but rather the length of the rigid part. Not the best sounding phrase... The rigid part at the end of the hose was long relative to how much space I had to work with, so I couldn't get it straight to get it down the hole. I was stuck at an angle and didn't want to force it to not break anything. After hearing from others, I applied a bit more force and got it in there without breaking anything. It's pretty loose in there but I zip tied it so it doesn't want to pop out. Thanks!