By Steven Pro
Air pumps are not utilized as often
as they once were. Back in the days before safe submersible water pumps were the
norm, all hobbyists had to operate the undergravel, box, sponge, and assorted
other filters for their aquariums with air pumps. That said, air pumps still
serve many useful purposes today. They can be used to operate air-driven protein
skimmers, which can be quite effective and efficient. They can be used for
sponge filters, which are exceptional for inexpensive and effectual biological
filtration for quarantine/hospital tanks, commercial fish hatcheries, or even
small home breeding and rearing setups. They can simply provide some
additional aeration or movement in a display. Last but not least, they can be
used to make little plastic treasure chest open and close or a small Sponge Bob
Square Pants dance underwater! Whatever your desires, there is an air pump out
there to meet it.
Most modern air pumps utilize an
alternating electromagnet to move armature that is connected to a cup shaped
diaphragm. The diaphragm pumps in and out much like a plunger. It has check
valves attached which only permit air to enter one way while being pumped out
another. This creates a reasonably steady stream of air. It also does this in
relative quiet, since the armature’s base, as well as the diaphragm is all
constructed of rubber. This isolates and minimizes vibration causing noise.
The first several pumps we will look at are diaphragm pumps.
The "Luft" pump is now sold under the
Coralife label. This is a quite, powerful and efficient air pump.
(formerly marketed under the Tetra label) Luft Pump:
These are by far my favorite air
pumps. I have used a large number of these for the past several years to run
air-driven protein skimmers as well as to operate sponge filters. They are
quiet, powerful, reliable, reasonably priced, and only use 5 watts! They even
come with a rheostat to adjust the air output. They cover all the bases of what
a good air pump should be and are the standard by which I judge all other air
pumps. <Editor's note- I have had a Luft pump in almost continuous operation
since I purchased it...in 1982!!- S.F.>
When these pumps came out about six
or seven years ago and they made a very good first impression. They were very
reasonably priced. In fact, they were some of the cheapest air pumps one could
buy. They were also fairly powerful. The downside is they were on the noisy
side. If you wanted to run a sponge filter for say a quarantine tank in a fish
room, basement, or other area that was not a common living area, they would be a
very good choice. But, if the pump has to be around people and quiet operation
is a concern, there are better choices.
"Old Faithful". Second nature
whisper pumps were reliable and easily serviced, but no longer seem to
This is yet another older air pump
series. I don’t believe they are still available, at least not from the original
manufacturer. I have heard that someone somewhere has the old molds and is still
making these pumps, but I can’t confirm this story. What I can tell you is these
were my favorite air pumps of the day. They came in a wide variety of prices and
sizes to fit most any need. They were reasonably quiet and reliable. They were
also easy to service and replacement parts, mostly new diaphragms, air filters,
and check valves, were widely available. Unfortunately, they were replaced with
the so-called ‘new and improved’ Tetratec line of pumps.
These pumps were initially more
powerful and quieter than their Whisper brethren. Unfortunately, their
diaphragms seemed to go bad quickly, losing power. Replacement parts are harder
to come by, and even if replacement diaphragms were easy to find, they would
need to be replaced unacceptably often.
These old school pumps are powerful,
but very noisy. Unlike the previous pumps which use diaphragm technology, the
Dynamaster has a large electrical motor which spins in one direction. The motor
is connected to two pistons which pump out alternating blasts of air. The
whirling of the motor along with the direct mechanical links to the pistons
makes for a noisy yet powerful pump. These pumps are fairly reliable and easy to
service. If one was operating a small fish room in an area away from the general
family living area, it is not a bad choice.
Whitewater Linear Piston Pump.... when
you need to move a lot of air!
Linear Piston Pump:
While definitely not for everyone,
these pumps are impressive. The smallest model I have seen for sale pumps out
2.5 cubic feet per minute. To get a sense of how much air these pumps
move, I use one of these models to operate twelve 1” airstones at 12” deep and
there is plenty of air pressure to spare. They are extremely powerful, but that
output comes along with a high initial purchase price and electrical usage. They
are also not the quietest units I have used. But, in all fairness, to recreate
the amount of air this one unit provides would require a small army of Luft
pumps. While one Luft pump is quiet, a dozen acting in unison might be something
else all together.
Whichever air pump you chose, there
are a couple of things you can do to make them function at their peak. For one,
don’t forget about preventative maintenance. The little air filters on these
units should be examined at least monthly and replaced as necessary. By
maintaining a clean air filter, the pump won’t have to work as hard to pull in
fresh air and can conversely pump out more.
Dirty and clean air pump filters.
Moving air moves a lot of dirt! Clean air filters help protect air
pumps and keep them quite and trouble free.
Also, take steps to minimize the
noise. Placing the unit on a soft pad can help tremendously. Computer mouse pads
work extremely well, as do small Styrofoam blocks (like the kind you can create
from broken fish boxes) or squares from leftover rubber pond liner. Fish keepers
are a resourceful lot generally. Reuse and recycle whatever you can.
By far, I like the Luft pumps over
most any other make and model. They are reliable, powerful, adjustable, quiet,
and reasonably priced. For larger applications, consider a linear piston pump,
or even a blower. But, for most hobbyist needs, the Luft pump will serve you
And, don’t discount air pumps out of
hand in favor of more expensive and sophisticated alternatives. I (and other
old-school aquarists) have a soft spot in my heart for air pumps. They is
nothing more relaxing to me than seeing a well designed fish room and hearing
nothing more than the soft, gentle sounds of bubbles in water. Definitely, don’t
knock them until you have tried them.