Equipment
Ok, can anybody explain to me, why you need more than a 1.5'' hole, for a 1-inch bulkhead? also, Why can you fit such a bulk head into a 2.5'' hole?
I am a complete, and utter beginner on plumbing, as in, I know what PVC is. So if there is some go-to website, video, etc. for aquarium plumbing...