Heat from a Mag 18

[Chin_Lee]

I use to have my Iwaki 70 as my return pump from the basement into my main tank and I had a Mak4 and a Mag 18 feeding my dual beckett skimmer.
Well thanks to all (esp Tang_man_montreal) who replied to my previous post inquiring about the gph of a Mak4 at 14' head...... this past weekend, I reconfigured my setup so that my Iwaki 70 is feeding both beckett injectors and my Mak4 as the return to my main. Naturally, the flow output into my main tank isn't as strong and i'm estimating about 700-800 gph turnover from the sump.
Anyways, the reason I am posting is because the Mag18 used to be submerged in my sump and the temp was at 80-81F without the MHs on. Now that the mag18 has been removed, the temp is at 78 steady. Considering that my system combined is approximately 320 gal, I didn't realize how much heat the pump was giving off. Keep in mind this was in a submerged application and I'm sure its less if used in-line.
For what its worth to those who have a submerged Mag 18........ I hope this will make you reassess your setup if heat is an issue.

BTW - I now have a Mag18 for sale in the B&S forum.