I'd be interested in hearing your experiences with battery-operated air pumps,
both back-ups for power outages
and portables for transporting fish.
I bought two portables on ebay
(I prefer to support local businesses,
but we live WAY out in the woods
and our closest pet shop doesn't carry these).
They are "Five Plan" brand
and the model is "Atom 2".
With shipping they cost about eleven dollars each.
These are strange little pumps.
About the size of a pager, they take two 'D' cell batteries,
though they run fine on a single 'D' cell.
They are described as 2-speed pumps,
and the second battery is necessary for the second speed,
though there seems to be only something like a ten-percent difference
between the 'Low" and 'High" speeds.
They are not powerful in the sense that the air flow diminishes rapidly
if the air stone is submerged beyond about 20 inches,
but in 16 inches of water they put out as much air
as my AC Whisper pumps.
They are exceedingly noisy;
anyone sitting next to the tank or cooler being used
will have a headache within half an hour
unless they are fans of heavy metal.
These pumps ship with an air stone and twenty inches of air line.
To my surprise, these are good enough that I didn't bother changing them.
I have used these pumps for a total of maybe three hours
and the batteries still seem like new.
I would buy them again,
though if I could find quieter pumps that would be a very good thing.
Does anyone have experience with the Azoo portable pumps?
To my experience the little battery powered air pumps (that take C or D cell batteries) for keeping fish alive in transport of bate alive in a bucket work fairly good though I've not put them to extensive use, just for bringing fish home without oxygen. They are noizy but not meant for running while you try to sleep.
I've never gotten the Azoo one since they are too small for anything I"m running that needs battery backup. I'm not sure if it's still the case but once upon a time the batteries were not replaceable so it seemed pointless to me to buy one.
For my large system air backup, I have a relay that will flip the pump over to an inverter that runs on a 100 + AH deep cycle battery that normally lives on a float charger and can run my big air pump for over 24 hours (I can hope that is enough time for power to come back on or for me to deal with a generator.)