Powerhead bubbles.. Is this bad?
Powerhead bubbles.. Is this bad?
I have a powerhead completely submersed in my 40G tank. Even though it is completely submersed, the outtake constantly puts out air bubbles with the outflow. So, where are they coming from? Am I driving CO2 out of my water column with this powerhead? Any thoughts?
Either the venturi air vent is sucking in a vortex of air, or the main intake for the powerhead is clogged and the pump is cavitating.
If the first, block the venturi air vent with knotted tubing or a shut-off air valve. Or lower the powerhead a bit deeper in the tank.
If the second, clean the prefilter or whatever is clogged.
Either can affect the CO2 if the bubbling is strong. If it is an occasional bubble, it is likely trivial.
If the first, block the venturi air vent with knotted tubing or a shut-off air valve. Or lower the powerhead a bit deeper in the tank.
If the second, clean the prefilter or whatever is clogged.
Either can affect the CO2 if the bubbling is strong. If it is an occasional bubble, it is likely trivial.
Where's the fish? Neptune
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Ghazanfar Ghori
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Hmm... It must be cavitation, since the powerhead is actually almost at the gravel level. I have a sponge on the intake. I'll give it a good cleaning, and report back. It's a Hagen 402 powerhead, so it can put out a pretty good stream of water, but I don't have it at the highest setting. Anyways, thanks for the ideas. I'll let you know how it goes. It is a steady stream of bubbles.
Sure a powerhead can cavitate. Just for yuks, is it less in the am and more in pm after the lights have been on for a while? Assuming it is, the water is super satuerated with O2 I'd imagine and the high pressure area at the impeller blade tips is squezzing O2 out of solution. Much the way a jet creates a con trail.
Nathan
Exactly as Nathan said! 
The hint for AM/PM bubble difference is elegant and valid.
The 402s and 802s are not wimpy little pumps in anybody's book. They are the only powerheads I use routinely as lift pumps. Cutting back on the flow is starving the pump itself to some extent. From lift uses I have done around here, very frequent sponge rinsing is needed in most setups.
The hint for AM/PM bubble difference is elegant and valid. The 402s and 802s are not wimpy little pumps in anybody's book. They are the only powerheads I use routinely as lift pumps. Cutting back on the flow is starving the pump itself to some extent. From lift uses I have done around here, very frequent sponge rinsing is needed in most setups.
Where's the fish? Neptune
