Return pump shooting micro bubbles

[dwair]

I have a Sicce 5.0 Silent pump as my return pump and something is blowing my mind, the water level in my return chamber is at least 2-3" above the return pump and it still will shoot out micro bubbles all in my tank. I cannot for the life of me figure this out. Its not sucking air cause its completely submerged. It doesn't do it constantly, like every 30 sec or so. I have zero leaks anywhere in my plumbing. Any ideas?

 

[Substantial Oof]

Are you running a skimmer?

 

[dwair]

Are you running a skimmer?

No

 

[aurora.k]

Is it creating a cyclone? Is that the right word in water? One of my return pump valves is placed at just such an angle that it creates a “cyclone” of air and pulls the air into the flow and then the cyclone disappears. It sends bubbles. I tried to move the valve but all my corals on that side objected,

 

[Billldg]

I have a Sicce 5.0 Silent pump as my return pump and something is blowing my mind, the water level in my return chamber is at least 2-3" above the return pump and it still will shoot out micro bubbles all in my tank. I cannot for the life of me figure this out. Its not sucking air cause its completely submerged. It doesn't do it constantly, like every 30 sec or so. I have zero leaks anywhere in my plumbing. Any ideas?

I have had my Cor 20's do the same thing. I found that if the water that is flowing the 2nd chamber in my sump is to high, vs. the 3rd return chamber, it will create micro bubbles in the return chamber and the return pumps will shoot it out. I have to keep a higher level in my return chamber of my sump to prevent this. Both of my Cor 20's are also submerged by a few inches.

 

[kenbennedy]

Could one of the return line plumbing fittings be letting air in between the pump and display tank?

 

[dwair]

Could one of the return line plumbing fittings be letting air in between the pump and display tank?

yes this has been my thoughts as well, but I can't tell anything as it isn't leaking. If air was able to escape wouldn't water be shown?

 

[dwair]

I have had my Cor 20's do the same thing. I found that if the water that is flowing the 2nd chamber in my sump is to high, vs. the 3rd return chamber, it will create micro bubbles in the return chamber and the return pumps will shoot it out. I have to keep a higher level in my return chamber of my sump to prevent this. Both of my Cor 20's are also submerged by a few inches.

yea thats not it for me, I've got no bubbles going to the return pump chamber. Also I can't really fill it any higher, I mean I could, I have the room, but Cade designed this with a gravity fed ATO. and the float value is right there, so If I put the water level any higher, the float value and therefore the ATO is useless lol.

 

[Billldg]

Just grasping at straws now, but what is the turnover of you sump? Just trying to think of some things that may create microbubbles.

 

[dwair]

Just grasping at straws now, but what is the turnover of you sump? Just trying to think of some things that may create microbubbles.

Well this is something I've never understood. I know you are supposed to have at least 10x turnover right? So its a 57g display, with a 13g sump. So 70g total. Not counting displacement from rock/sand in both fuge and DT. The Sicce 5.0 Silent is rated at 1321GPH. I also have a Nero 3 running between 50-75% which is over 1300 GPH. But I also have a ball value on my drain line choking it down to keep it quieter plus avoiding bubbles. So to be completely freaking honest @Billldg I have NO idea lol. I say I have good turnover, but honestly with all the displacement, plus the ball value choking it down, I couldn't tell you. I've never understood how people figure that out. Guess I'd need a flow meter?

 

[Evo R]

Is it creating a cyclone? Is that the right word in water? One of my return pump valves is placed at just such an angle that it creates a “cyclone” of air and pulls the air into the flow and then the cyclone disappears. It sends bubbles. I tried to move the valve but all my corals on that side objected,

This was my first thought too. You could always test it to see if its making a cyclone/vortex/tornado above the water intake of the pump.

Saw a vid of someone showing the tornado affect above a mp40 which was very close to the water surface. And to demonstrate the effect, he poured small amounts of Red Sea AB+ which is that neon green color right above the wave maker. On the second or third attempt he caught it on video.
Out of nothing a small tornado/vortex/cyclone formed from the water surface and as it grew downwards got longer and the moment it touched the mp40 it would send micro bubbles everywhere and the vortex was broken. It would happen erratically and only last a second or two.

 

[Billldg]

Turnover thru the sump only deals with the return pump, none of the flow pumps and such matter. Its the flow that will run thru a filter sock, if you have them. This is were head height and such will effect the return pump itself. 10x turnover was the thinking a while back, but now, many feel that 4x-5x is more than enough. I try to keep a 4-5x turnover in my tank as well. I am wondering if to much turnover in the sump is creating microbubbles that are being caught by the return pump. Again, just trying to think of something that has not been thought of yet.

 

[dwair]

This was my first thought too. You could always test it to see if its making a cyclone/vortex/tornado above the water intake of the pump.

Saw a vid of someone showing the tornado affect above a mp40 which was very close to the water surface. And to demonstrate the effect, he poured small amounts of Red Sea AB+ which is that neon green color right above the wave maker. On the second or third attempt he caught it on video.
Out of nothing a small tornado/vortex/cyclone formed from the water surface and as it grew downwards got longer and the moment it touched the mp40 it would send micro bubbles everywhere and the vortex was broken. It would happen erratically and only last a second or two.

I don't think this is it. I feel like you'd hear it wanting to suck air. I've done that with an MP40 in the past as well, but mine was during a water change, so I know what you are talking about. I've seen the cyclones. But when the MP40 did that, it made a distinct sound as well when it grasped a little air from that.

 

[DCR]

Pumps develop less pressure inside the pump which can cause degassing of dissolved air that may not go back into solution. It builds up on parts of your return plumbing until it gets large enough to be expelled in a one shot. It could also just be due to very small entrained air bubbles that are collecting in your return piping. You do not have to create a vortex or cyclone to get air ingested. The solution in most any case is to raise the water level and/or eliminate any waterfall over a weir into the pump chamber.

 

[dwair]

Pumps develop less pressure inside the pump which can cause degassing of dissolved air that may not go back into solution. It builds up on parts of your return plumbing until it gets large enough to be expelled in a one shot. It could also just be due to very small entrained air bubbles that are collecting in your return piping. You do not have to create a vortex or cyclone to get air ingested. The solution in most any case is to raise the water level and/or eliminate any waterfall over a weir into the pump chamber.

Ok I do have a small waterfall it’s the design of the sump though. No real way to kill it without killing my ATO. I took pics to show. Plus you can see how far above the return pump the water level is now.

 

[Spieg]

Well oxygenated water is subject to cavitation at the impeller. Usually turning down the speed will cure this.

 

[dwair]

Well oxygenated water is subject to cavitation at the impeller. Usually turning down the speed will cure this.

I've got the pump set on the lowest speed already.

 

[Marco Vasquez]

I have a Sicce 5.0 Silent pump as my return pump and something is blowing my mind, the water level in my return chamber is at least 2-3" above the return pump and it still will shoot out micro bubbles all in my tank. I cannot for the life of me figure this out. Its not sucking air cause its completely submerged. It doesn't do it constantly, like every 30 sec or so. I have zero leaks anywhere in my plumbing. Any ideas?

Can you post pics of your setup?

 

[dwair]

Can you post pics of your setup?

I did above this post.

 

[Marco Vasquez]

I did above this post.

Sorry about that. Thanks…