A couple of days ago I tried a quick needle wheel mod using a 1000lph powerhead I had laying around. I'm sold; easy to maintain, easy to implement, and very effective. But I hate having equipment in the tank and don't want to use an external pump that would require its own inlet/outlet.
Instead I'd like to run a small pump on a parallel loop from an Eheim 2028. The filter should supply enough flow to disperse the mist, so the only real requirement is that the pump's powerful enough to smash the CO2. An Eheim 1046 or 1048 would work, but I also noticed the 1005, which is the size of a small powerhead, pumps only 270lph, and can be used externally like the larger Universals.
The question is, would the 1005 be too wimpy for the task?
It's funny you mention the UP atomizer, because that's one of the other options I looked into. But while they seem to be very effective, I also found a few posts about the quality control not being very good.
Problem is, my little ol' bad back can't take moving around monster filters like the 2080, 2260, or FX5... yet in my infinite wisdom I chose to have a 125 gallon. So I'm already running two Eheim 2028 and two Eheim 2217 on the thing. And it's not drilled, so that's four inlets and outlets! A fifth set for a separate pump loop might just make my head explode.
I'd be comfortable running a small pump in parallel with taps to fine tune the flow rate. I'm just not sure how small a pump I could get away with using.