I'm planning my 40g breeder sump/refugium right now and was wondering about pump placement. I have about 36" to work with and I'm leaving 10" for a future, larger skimmer. Add in 2 baffle areas and I'm down to about 22"-24". I'm probably going to invest in an Eheim 1260 or 1262.
I'd need to leave about 5" or more for the return pump area. I see a lot of DIY sumps with the pumps submerged (including my first FW
sump build). Given they can give off heat and would take up 5" on the sump, wouldn't I benefit from designing this without a submerged pump?
What are the cons of an out of water pump, especially with the Eheim models?