bubbles in tank whats the cause?

[fijiwigi]

I am trying to understand exactly what causes the little micro bubbles that attach themselves to the glass to the rocks and even to algae. Are the bubbles from too much oxygen, Too much flow., whats the science behind the underwater bubbles.

 

[ccCapt]

Are they coming out of your return line? I've seen bubbles attached to glass on new tank setups, but your tank has been running for a while and shouldn't have anything like that. If they are coming from the return, you pump may be cavitating. Is the pump restricted at all? Valve either before or after it? Cyano will also produce bubbles under it, but what you describe doesn't sound like that.

 

[fijiwigi]

There was bubbles last night all over the glass. and this morning there is barely any. I did adjust my pump. I have 2 ball valves controlling my return pump 1 on the return line and 1 after a tee that returns into the return zone as not to restrict the flow of the pump. The return zone valve is open just a little bit and the valve on the return line closed just a little bit.
And what is cavitating exactly.

 

[cmor1701d]

Cavitation "The vacuum created when the discharge capacity of the pump exceeds the replacement in the suction line. This causes bubbling and vibrations that can damage the pump if they occur over an extended period."

This could be from a powerhead or a return pump that needs to be cleaned.

 

[ccCapt]

The way I understand it, and this is probably as basic as it gets, is if water doesn't flow freely and unrestricted thru the pump, an area of higher (or lower...not sure...lol) pressure develops around the impellor and forms bubbles, which are then pumped into the tank.
Same as cmor said...I think.

You should have one of those valves open all the way. Maybe open the valve to the tank all the way and open the other as much as is needed to slow down flow into the tank...if that's what you are trying to do.

 

[pat8you]

I'm fairly sure the motion of the impeller causes a lower pressure which normally the makers of the pump account for so it doesn't form any bubbles but when the flow is restricted like cmor said that also lowers the pressure and the combination of the two probably causes cavitation. But if that is whats going on you should look into it because something seeming harmless like bubbles can wreck your pump up pretty bad.

 

[fijiwigi]

I have only had the pump running for about 3 days. Still trying to tweak everything to get it just right. Tonight when I got home there was very little bubbles just about 20 extremely small ones behind my hydor koralia's.

 

[cmor1701d]

Could have been trapped air bubbles in the new pump. Glad to hear it's subsiding. Cavitiation in any pump will ruin the impeller. It a problem in boating and especailly in jet skis.