Bubbles out of my return

Discussion in 'Filters, Pumps, etc..' started by Ryan Duchatel, Mar 11, 2013.

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  1. Ryan Duchatel

    Ryan Duchatel Millepora

    Joined:
    Jun 11, 2012
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    Location:
    Newcastle, AUS
    Hey all,

    Background:
    Some of you already know that I have some bubbles coming out of my return from my sump.

    Cosmo has already had a stab at what could be causing them and how they can be prevented, but sorry cosmo, im a little lost :) haha.

    Implication:
    They never really bothered me until recently, I have had two power shortages on my light, causing the battery pack to be replaced. This time I have to send the whole light back and one of the things the manufacturer said could be causing it is moisture getting into the fixture because of bubbles. I think this could be the case (as I have an open top) that the return bubbles have caused moisture to get into the light. If this is truely the case, I may have to pay to get a replacement. Which is going to put me out like $800.

    So better get on top if it now.

    The culprit:
    My return is an Ehiem 3000 in the return section of the sump. I have PVC joined onto the top, which is not a tight fit but a loose fit as it doesn't seem to connect properly? All the PVC is glued. I have an siphon break drilled into the top that is above the water line.

    Any help, prefereably with a picture or two would be very very very beneficial :). Thank you very much in advance.

    Ryan.
     
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  3. Greg@LionfishLair

    Greg@LionfishLair 3reef Sponsor

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    Based on what you're saying, I'd suspect that your loose connection is sucking air, assuming it's exposed. What do you mean when you say "it doesn't connect properly"? What kind of connection is it?

    Do you have bubbles in your pump bay, such as from the water falling into it? If so, they're likely getting shredded by the pump's impeller.

    Also, try plugging the siphon break just to see what that does. I never run siphon breaks out of the water personally...they're always 1/4" to 1/2" below the surface. I suspect that's what gave your lights a bath. You can add a small 90* nipple on it so it doesn't squirt straight up (use one of those airline T's).

    Is the return line in your DT out of the water, or under it?
     
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  4. Ryan Duchatel

    Ryan Duchatel Millepora

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    The loose connection is under the water. I think the connection size is 1/4 inch or so, and the pvc is 1/4 but it still wobbles around on top. Its not tight like a flexi hose is.

    There are no bubbles in my return section, I have loads of baffles etc to stop bubbles moving between sections.

    I am not sure how to plug the siphon break? With sticky tape?

    The return line is to the DT is under the water.

    If you have any idea how to make the PVC connect really tight to my pump then I could just re-do the return piping?
     
  5. HeiHei29er

    HeiHei29er Gigas Clam

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    Houghton, MI
    If the loose connection to your pump is underwater, then it's likely no tthe issue.

    +1 on plugging the antisiphon as a start. Yes, tape should work fine.
     
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  6. DevinH

    DevinH Montipora Capricornis

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    I'd put a spot of glue on it.
     
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  7. Nuebie

    Nuebie Peppermint Shrimp

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    +1 on the siphon break being 1/4" below the water line.
     
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  9. Scuba Ken

    Scuba Ken Ritteri Anemone

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    what does the impeller look like ? is it damaged ? couyld it be turbulance thats causing the bubbles and not air ?
     
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  10. AZDesertRat

    AZDesertRat Giant Squid

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    Your drilled hole is acting like a venturi and sucking air in.

    Forget the drilled hole, its a false sense of security anyway and unnecessary. Keep the return close to the surface so only a very small, easily calculated amount of water returns to the sump in a power outage and keep that much freeboard in the sump at all times and a flood is not possible. Once the return is exposed to atmosphere the siphon breaks and we all know water cannot jump uphill so it is not possible to flood. Plug the drilled hole, keep the return 3/4" or so below the surface and leave a few galllons of spare room in the sump and you are good to go. No cleaning, no maintenance and no floods so you can sleep soundly at night.
     
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  11. SeminoleB

    SeminoleB Coral Banded Shrimp

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    +1 to this! If the Eheim was the culprit, you would have to suck the air in on the intake side of the pump. Once through the pump, you are on the pressure side of the pump and would be spitting water out if there was an issue with the plumbing
     
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  12. Todd_Sails

    Todd_Sails Giant Squid

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    Agree on the siphon break hole.

    Either plug it and keep the return nozzle just under the surface, OR

    Put the siphon break hole about a 1/4 inch UNDER the surface- that way, no spray, bubles, etc.

    Also- could that loose fitting in the sump actually suck air? Doubt it unless it's not under water, it should be leaking some of your return flow, if it's leaking.

    This is asuming it not sucking micro bubbles from your skimmer.

    $800 for a replacement light? Too much IMHO
     
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