Return pump shooting micro bubbles

[Marco Vasquez]

Your pump is pretty shallow. My only thought is that you are getting a vortex every few moments. Can you place a sheet of plexiglass or glass horizontally above the pump to divert the water more broadly?

 

[Supa]

Mine does the same thing after it turns back on it will occasionally spit bubbles then go back to normal sometimes spits bubbles every 5 minutes or so. I think it’s due to the levels in the sump having to equal out properly before working again.

 

[dwair]

Your pump is pretty shallow. My only thought is that you are getting a vortex every few moments. Can you place a sheet of plexiglass or glass horizontally above the pump to divert the water more broadly?

How is it shallow? At least 3-4 inches above the pump?

 

[Marco Vasquez]

How is it shallow? At least 3-4 inches above the pump?

Vortex can go that deep.

 

[ying yang]

Something is causing micro bubbles before the return pump and its getting trapped in pump then when big enough its spits large bubble out your nozzle which disperses into smaller bubbles.

Another possibility is that air can leak from a pipe but not water if somewhere not sealed properly and in this application air can get sucked into a pipe if small part tubing not sealed.and then go with the flow of water that return pushing back into dt.

But as you say you got a waterfall part of sump i suspect coming from here.( at night time try turn video on phone with light on and place onto sump glass and try zoom in and see if can see micro bubbles coming from waterfall before it hits return pump.if it is this you could add a bubble trap of some kind like foam/course fibre stuff like have in freahwater filters or some filter floss but would have to make sure doesnt get to clooged and slow the flow down etc.
Another option mess around with return pump speed and make fast for few seconds then dial back down to where you want it.
Also could add a baffle if it is micro bubbles before return pump..
But also as someone mentioned you got something that happens called cavitation but without googling it i forgot exact specifics of how and why it happens pfft
Good luck

 

[dwair]

Well I tried what @Billldg did and upped my water level in the sump. Stopped the waterfall completely and low and behold, haven't seen any bubbles yet for at least a couple of hours. What sucks is, my gravity fed ATO that Cade designed for this is now utterly useless. I'm going to have to put my old Tunze ATO on here and find an ATO container. Cause Cades is built into the back of the tank.

 

[G Santana]

I have a sump with no baffles and I battle this all the time. One, in order to avoid my pump creating a cyclone, I have to insure that my water level is maintained high enough to avoid the pump pulling air. That I solved with an ATO.
Second, I insure that anything returning water into the sump does so under water. This helps avoid micro bubbles but doesn't eliminate them, lastly i made a plexiglass screen that I have filter floss right before the pump intake that helps stop micro bubbles from going into the display.
Hope this helps.

 

[Billldg]

Well I tried what @Billldg did and upped my water level in the sump. Stopped the waterfall completely and low and behold, haven't seen any bubbles yet for at least a couple of hours. What sucks is, my gravity fed ATO that Cade designed for this is now utterly useless. I'm going to have to put my old Tunze ATO on here and find an ATO container. Cause Cades is built into the back of the tank.

I read thru the rest of the thread, and it reminded me that you can also try something else, and maybe, keep the water level at the same height as you normally kept it at. I installed a thick filter, that was originally meant to be used to filter debris before hitting the return pumps, between the 2nd and 3rd chamber to help settle any bubbles. Is their anyway of adding such a filter. I would, maybe, try to lay a filter across the top of the section that allows the water to flow from one chamber to the return pump chamber, and see if that settles out any microbubbles.

 

[dwair]

I read thru the rest of the thread, and it reminded me that you can also try something else, and maybe, keep the water level at the same height as you normally kept it at. I installed a thick filter, that was originally meant to be used to filter debris before hitting the return pumps, between the 2nd and 3rd chamber to help settle any bubbles. Is their anyway of adding such a filter. I would, maybe, try to lay a filter across the top of the section that allows the water to flow from one chamber to the return pump chamber, and see if that settles out any microbubbles.

I actually have been doing that for the past month in an effort to stop the macro algae I had in there from going into the return pump. Still had bubbles. But I’ve since removed it cause now I only have Chaeto in there and it doesn’t move.

Think that only upping the water level is going to solve this.

 

[Spieg]

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?

Just did some research and it appears this is not a DC controllable pump. All you can do to turn it down is turn a knob on the pump housing to block off some of the input. This increases the negative pressure in the impeller chamber and promotes increased cavitation (makes more bubbles). You simply have way more pump than you really need for your tank. I'd recommend replacing with a much smaller (maybe 1/3 - 1/2 the flow rate) pump and you should see the bubbles go away.

 

[pup1477]

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?

Mine was doing the same thing, I did a 10% water change and they went away not sure if that was the problem but they did go away