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Air ring main for aquarium

  1. Mar 10, 2012 #1
    Hi there

    I don't know if this is the correct forum to be posting in, but I am sure that with all the expert physics gurus on here, someone can help me with this basic project.

    I am trying to build an air ring main system for an aquarium.

    I previously had the system setup as follows:

    http://img843.imageshack.us/img843/1549/ringmain1.png [Broken]

    The Brown Box represents the Air Compressor. The Blue Boxes represent the Air Stones.

    A friend suggested I design a ringmain for better performance, as I was going to be experiencing 'drop off' in the pressure between the first and last air stones.

    I therefore made the following setup:

    http://img31.imageshack.us/img31/6917/ringmain2.png [Broken]

    What I am finding now is that I am getting increased air supply through air stones 2 and 7.

    Any suggestions on how to best design the ring main in order to supply an even air supply to all air stones.

    Is the fact that I have dual supply lines an issue? Is there a conflict caused at the red indications on the diagram?

    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Mar 12, 2012 #2


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    If you look again at your two pictures you will notice that the air supply goes to stone 1, then 2, then 3 for both, so you still get the dropoff from first to last stones with the air ring. All things being equal the length of tube between the dual supply lines and the tube between stones 4 and 5 are superfluous.

    If stones 2 and 7 exhibit too much air then use a smaller diameter tube from the main line to these two stones.
  4. Mar 12, 2012 #3


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    Compressed air or water - you would normally see such a system using a manifold to distribute the flow (pressure) evenly to the drops.

    My (intuitive) suggestion... Try a manifold that has slightly more cross sectional area than the sum of all the drops.
  5. Mar 13, 2012 #4

    jim hardy

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    Quick check on sensitivity to elevation: Put 2 & 7 slightly deeper than others and observe result.?

    I would think you'd want them all same distance from compresor

    feed compressor's two output tubes into middle of your lines 1-4 and 8-5, using equal length tubes.
  6. Mar 18, 2012 #5
    Hi guys,

    Thanks for the responses.

    256bits - I am using as small a pipe as is possible, 5mm silicon tubing.

    Bandit127 - I am sure that a manifold or multivalve pump would work perfectly, but I was trying for as cheap a setup as possible ;-)

    Jim hardy - Thanks, your suggestion seems to have worked. I have now recofigured the ringmain as follows:
    http://img21.imageshack.us/img21/6917/ringmain2.png [Broken]

    I seem to be getting much better and even air flow from all air stones currently.

    Last edited by a moderator: May 5, 2017
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