"Joseph Thomas" wrote in message
Can anyone offer advice about an air pump? Do I need it at all? If
not, is it sufficient just to have surface agitation caused by the
filter? I'd really like to do without the noise and bubbles if
possible. I'm not happy with the advice I was given so far, which is
to wait and see if the fish appear to be 'gasping' for oxygen to get
my answer.


I have a 90g planted aquarium that has only an Eheim cannister filter. I had
terrible heat build up until I realized that in trying to minimize surface
agitation I had very nearly choked out *all* the water circulation. I
redirected the spraybar up at a bit of an angle- not enough to break the
surface but enough to cause a slight rippling effect.
The fish are loving the new water circulation, plants are doing better as
well, and the temperature went down 3ºF.

--
Toni
http://www.cearbhaill.com/aquarium.htm