I was thinking about getting one of these diffusers but had a couple
of questions. Do they sit inside the tank or outside the tank ? Okay,
maybe that's a dumb questions, since I assume they have to be inside,
however, are they very large ? Do they look ugly ? I am trying to make
my tank look natural and having a giant plastic thingy in the tank
would seem to defeat the purpose.



On Mon, 31 Mar 2003 01:49:35 -0600, Eric Schreiber
wrote:

"Dave" wrote:

I recently set up a 33 gallon planted tank and purchased one of these
Nutrafin thingys. I have a few questions about the bubble dispenser that
attaches to the side of the tank with suction cups. Are the bubbles
supposed to flow directly out of the airtubing into the dispenser?

Yes, they are.

Sounds like your tube may not be set in place quite right. The end of
the tube should have a little plastic nozzle thingy, cut at a slant.
The direction of that slant will steer the bubbles into the diffuser.

From there, the bubbles should zig-zag through the entire diffuser
from bottom to top, before finally floating out the top.

attached a small pce of plastic to the bottom to guide the bubbles directly
into the dispenser. When I did that....all the bubbles went directly into
it....and then flowed up each level of the dispenser...and then flowed out
the top of it to the surface and popped. No bubbles actually stayed in the
dispenser...they just flowed out level by level up to the top.

Bear in mind that when you first start up a new CO2 mix, you've got
mostly regular air in the CO2 bottle. That regular air has to be
forced out by CO2 production first, and it can take up to a day to do
that. Since your tank water is reasonably well saturated with the
components of regular air, these starting bubbles will remain pretty
much the same size as they travel through the diffuser.

However, once the regular air has been cleared from the CO2 bottle,
you'll start getting more-or-less pure CO2 gas. When these bubbles
travel through the diffuser, you'll see that they actually get much
smaller and slower by the time they reach the top.

This shrinking of the bubbles as they move through the diffuser is
your verification that CO2 is properly dissolving into the water, and
that the CO2 system is working correctly.