"KurtG" wrote in message ...
http://www.aquariumguys.com/silentairpump.html

I've heard that these pumps are a good investment for power outages
(which we frequently have in my locale).

The book that I'm reading implies that with a tall tank (like mine) and
lots of live rock (like mine), that the fishes could suffocate fairly
quickly.

Any comments?

That is quite true - the amount of biological load in a tank with live rock
is really substantial as demand for oxygen... That is why the agitation
of the water is really important to provide good gases exchange...

I am not sure if such air pump suffce - I have my tank protected by
a set of marine deep cycle type of lead acid battery, DC-AC
converter and a 3-way relay with a 120AC relay coil. All is hooked up
this way that relay coil is my AC detector: when the coil is engaged than
the relay is passing through AC wall electricity, normal mode. When there
is a power outage the relay coil disengages and closes contacts turning
the inverter (DC-AC converter) on and connects load circuit from
wall to the output from inverter. That is why I needed 3PDT relay type.

The inverter runs only limited number of the most imporant devices
including skimmer and circulation pump for acurate gases exchange.

Skimmer is running on MaxiJet 1200 (20W) and the circulation pump in
the sump is the QuietOne 3000 (40W) so my backup electricity source is
loaded with only about 60W and can deliver this much for a very long time.

Do not back up heater or lights - tank can survive no lights and temp
drop quite easily but water movement and gases exchange is critical.