Using a linear air pump in a wet dry sump system for return...

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

Mid posted......

On Mon, 28 Jul 2003 12:24:20 -0400, "Jim Brown"
wrote:


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.

The guy told me but I had "Tim the Tool Man" syndrome.... He offered
me a smaller one, but I couldn't resist....

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.

I had a feeling it would be... On the other hand, I would have been
running the smaller piston pump + a water pump of atleast 900GPH to
1000gph (the top tanks are pretty high so I have to compensate for the
head)... I'm hoping this will be cheaper then that combination, but I
might be mistaken since I've no idea how much power the water pump
would require... This pump is rated at around 54 Watts I think...

There may be a lot of splash at the return, so consider an elbow or 'U'
fitting to minimize.

I plan to have an elbow at the top leading to a horizontal pipe w/
ball valves or check valves over each of the three top tanks to
facilitate return..

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.

The output on the pump is pretty wide... (i think its 1/4" or more but
i'm too lazy to go to the garage to check)... The guy I bought it from
have an identical one w/ the appropriate sized flex tube leading
directly to a wall mounted pvc conduit pipe approx. 6 to 7' long... He
had it drilled at regular intervals w/ air valves inserted. From this
point he had regular airlines from the LFS leading to his various
UGF's and sponge filters. ( I think he had like 15-18 things running
and he still had to bleed it off)... Even he admitted that he did a
fairly sloppy job w/ a lot of the connections, but despite enough
leaks to qualify as a Ford, it was pushing his 180 GAL and atleast 5
other tanks quite well... Should I use wider airlines all the way in,
or can I use the regular stuff after the pvc?


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.

I can't picture that... Could you elaborate please :-)

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.

I'll look them up... I'm, a fairly recent addict.... er.... I meant
HOBBYIST!!!!

Just think it out, maximize the air supply tubing, and consider damage
control.

I'm puttin it all in the garage!!! (Next project is to insulate around
the whole system!

Thanx Jim! As always, you are a veritable font of wisdom! How are you
faring these days? Have you got your systems up to snuff again?
Cheers!

Madd Hatter


Jim