interesting idea...
I've run a submerged MAG pump (7 i think, or 9) on a skimmer and I can tell you that the majority of the noise on my system was gone when I turned off the skimmer (but it WAS sitting on the bottom of an acrylic sump)..
as far as heat goes.. my heater NEVER turned on when I was running the mag for the skimmer and the external blue line hd40-X pump..
I've got the apex logs to prove it..
Now that I run everything off the Reeflo pump (which runs at a lower wattage) the heater turns on every couple hours (albeit intermittently)
the cabinet doesnt' get warm on me, but then again, my particular cabinet has two HUGE openings at the back (at least 24"x24").. so I dont know it would get hot, otherwise..
I can also tell you that my mag pump would (at times) get so hot that it was VERY warm to the touch (in the water)... even uncomfortable to hold at times.. (still within the water)..
I'm thinking about doing a (probably unscientific) test...
