check this thing out - - i know space is a premium in your tank - - don't know if it helps but it looks cool.......lol Boss

http://www.marinedepot.com/ps_AquariumP ... lters.html

Hehe, as cool as that thing is I think its overkill. lol I tried to find some dimensions for it to give me a better picture of how much space it would take up in my 5gal but wasn't able to find much, don't need a heater anyway, the enclosed hood acts as a radiator when the freaking lights on. lol
I've been scouring the net to find some sort of powerhead that I can regulate the flow of between 25 and 75gph, is about the size of a whiffle ball, and I can toggle aeration (don't need it) on or off with, which just doesn't seem to exist, unless I'm not reading things right.
Still my only concern with using something like the ARIO from Hydor (the mini in-tank aerator) is creating tooo much surface agitation. Co2 will be crucial in this tank as I plan on getting dwarf baby tears and overhauling the existing plants (I was still a beginner when I got plants for this one..my java fern and anubias are planted in the substrate..
I know I need something though. Maybe a supplemental filter really would do the trick, all I know is this integrated thing sucks. There's a constant nasty film on top of the water which remains after every water change and thickens as the week progresses. The surface of the water barely moves.

Wouldn't you be increasing the co2 by running atmospheric air through the tank during the day when the plants need it? I thought that without supplemental co2 your plants will actually pull co2 in the water down to a lower level than what's in the air, which means that you'll be increasing co2 with an air stone. This is certainly smaller than a power head. It's when you have supplemental co2 that you don't want a bubbler. That will be a situation where atmospheric air has less co2 than your tank water and would blow it off. I think that a bubbler is what you need here and it will break up the film building up on the surface and increace o2 at night when fish can be in trouble in planted tanks. I have heavely planted tanks without co2 myself and the plants grow fine with lots of bubbles. I use powerheads with the air venturi on full. I'm even growing mocrosword in my 35 gallon long as well as java moss, fern, anubias, 2 varieties of larger sword, and others.

Ummm. I want to be sure about this as I didn't think of the fish adding co2 part of the equation. I asked this question in a forum where there are serious plant growers who use co2. I don't think the fish would produce enough co2 to keep up with the amount the plants absorb during the day, but to be sure I've put this question out to some "experts". I do have success growing the same plants you are growing w/o supplemental co2 and I have powerheads with the venturi's on full and I think I'm right but I want to be sure. I'll post the responses ASAP.