The Madd Hatter wrote in message
...
Ok, the title sucks....

I am working on my multiple tank system (6 tanks on a rack)... I just
bought a Medo AC0602 Linear piston pump to run my sponge filters and
everything else in 6 to 8 tanks that are between 14" to 18" in depth..
This pump is powerful enough that even if I ran 15-20 outlets at those
depths, I'd have to bleed air off to avoid turning my tanks into mini
hurricanes. Here is my idea... The tanks are all drilled w/
overflows.. I was planning to filter them with a common trickle style
sump system. This type of system usually has a water pump to return
the water back to the tanks.. I want to use my air pump. I plan to
make the return pipe a vertical pvc pipe (around 2" ID) w/ a hole near
the bottom to attach my air line... I figure this will function
similar to a lift tube in an undergravel filtration system, whereas
the water will get pulled up the tube, right to the top where I will
have a connecter routing it through another pipe w/ ball valves to
dump water back into the tanks... I realize this wouldn't work w/ a
conventional air pump, but i tested the lift tube idea in my buddy's
180GAL tank by standing up a 5' piece of 2" ID piping in his tank,
with my air pump output tube (1/2") shoved through it... As soon as we
turned the pump on, the water gysered a good 3' into the air... We
only left it plugged in for a split second.... though I think it would
have gone over 5' if left longer...

I figure the pressure will be there.... What I want to know is, will
this work? Does anyone know of anyone using a system like this? Good
idea, bad idea? Any ideas welcome at this point!\

thanx


Obviously, a pump with that much pressure was probably a bit of overkill,
but you seem to know that now.
Provided the air will do all your tanks, the option should work. The
downsides:
cost of pump and electricity are high when compared to water pumps
adequately sized.
There may be a lot of splash at the return, so consider an elbow or 'U'
fitting to minimize.
To get full benefit of the air volumes, you might want to consider larger
tubing. Even then, I would consider rigid piping to better handle the
pressure. You might also want a side pipe higher than the tank's surface to
eliminate any overflow problems if a power outage or pipe separation occurs.
What you are doing is just a very large version of the old HOT air driven
filters that were fairly popular a number of years ago.
Just think it out, maximize the air supply tubing, and consider damage
control.

Jim