On 8/7/03 9:25 PM, in article jUCYa.31013$ff.10558@fed1read01, "B."
wrote:

I am also looking for a good diffuser for my tank (55 gallon). I would like
to get one that doesnt waste any co2. I have tried building my own but they
just don't seem affective. I am currently diffusing with a powerhead but my
tank seems to empty alot quicker then it did with other methods. if you
know of any diffusers please let me know what the name is or where i can get
some info on it.

I've made a few different diffusers, mostly variations on countercurrent
siphon bell types, which usually work well but don't tend to stay in place,
look ugly, and take up a lot of space. The contraption I'm currently using
isn't really something I've seen much, but as long as I don't let the filter
get clogged, it's quiet efficient.

I've got a powerhead hooked up to a quickfilter, there's two slots in the
top of the filter attachment, the CO2 hose runs through that and connects to
an airstone, this sits in the top media basket of the quickfilter. The
powerhead output goes across the top of the tank in some siphon tubing, down
to the bottom on the other side, then connects to a spray bar down around
gravel level that points back in the direction of the powerhead. Kicks up
your gravel a bit, but provides good circulation at the bottom of the tank,
so less crap settles. If the filter gets clogged, the powerhead won't have
the force required to get most of the water down to the bottom of the tank,
and most of your CO2 will bleed out of the top hole.