When I first started reefing a lot of people told me that a 1 inch drain would only handle 650 to 700 GPH. I also saw that number posted on a lot of the forums. I don't know what nudnik decided to be cute and throw those stupid numbers around but they are totally false and a plague to this hobby. I have a single one inch drain and a 1 inch emergency drain, my ecotech l1 has 1 45° bend going up 2ft directly into my return. The single one inch drain pipe handles it with no problem and that's with multiple 90° bends.
Yeah that's where my concern was coming from I was seeing a lot of people saying those type of figures on forums, particularly ones over here in the UK. Thanks very much for the reply!