Bubbles normal???

[fishlips12]

I am using a Mag 7 pump for my return in to a 55 gal tank. I do have very minute bubbles probably 1/4mm coming out of the nozzle that makes the visiblity a little less than perfect. Is this normal? I made sure that there is very little turbulence at the inlet of the return pump but still get these small bubbles.

 

[BillyZ]

when looking at your sump, does there appear to be bubbles in the water near the intake? If that's the case you'll want to determine where those are coming from and see what you can do to stop that. Likely cause is a skimmer is letting bubbles back into your sump. If not, then, is your mag 7 in the tank or plumbed outside the tank? if it's outside there may be a small leak sucking air into the line.

for either the skimmer or the pump (if submerged) a sponge could help you out. on the skimmer out flow it could collect the bubbles, or on the pumps inflow could also help.

 

[toddwess]

I have the same problem. I have a submerged 500 gph pump in my sump with a sponge on it, and there are always tiny tiny tiny little bubbles comming from the power head. I also have a foam sponge on the overflow intake, and again after the water makes it through the sump.

As water spills into the surface skimmer, it makes bubbles, but these bubbles are stopped by the sponge on the other side.

Then the water travels down what looks like a vaccum cleaner hose into the sump. Where the water comes out there, there is also a TON of bubbles cuz that is where the protien skimmer is.

This water overflows to the bio-ball region and then through another sponge before entering the area where the return pump is. The return pump has a sponge on it, too.

And I still get tons of tiny bubbles coming out of the PH.

I really would be interested to see how to make this go away.

Todd

 

[fishlips12]

I agree with Billy Z there can only be two major sources of bubbles either air sucking in to the plumbing between the output of the pump to the tank or air bubbles present at the intake of the pump. I recall from my college days though that the fluid flow within the plumbing mentioned above , is in the turbulent fluid flow regime and bubbles will form because of this. If it were truly a laminar flow condition then I believe you would not see this phemomena. I mean these bubbles are very (.25mm at most).

 

[BillyZ]

I don't have a setup like this myself (yet, it's still being constructed) so I don't have any first hand exp to help out. I know I've seen this discussion on here before however. Try doing a Searc for "bubbles in tank" or "bubbles from sump" etc. You should find it somewhere.

Be sure to post back so we know what worked for you.

 

[dogofwar]

I'm gonna take a guess at what the prob could be besides bubbles entering the return pump.

With a prefilter and a high capacity pump, I could see a problem. Now as far as pump rate and the micron filtration specs I haven't a clue.

but this scenario is called cavitation. It happens when water is pulled through too fine of a filter at too high of a rate. Not only does this create bubbles but it will actually strip the water of it's oxy. The bubbles being created are the air within the water being seperated from it.

this situation could be witnessed by screening the intake on a propulsion type watercraft (jetski)
I'm sure it could also be demonstrated by screening the intake of a pump or PH.


I would remove the filter and see what happens.

 

[pm64971]

Further to that note, remove the filters and turn down the flow rate. The speed of the water is the largest factor in creating cavitation. Strickly from a fluids engineering point of view, it would be better to have more small flow rate PH than a few high flow rate PH that cause cavitation.

On a similar note, is it bad to have bubbles in your FOWLR tank? I've seen people bubble air up through the tank via a compressor; is this a bad idea?

 

[BillyZ]

the only problem I could see on a FOWLR coule be trapped air in the LR can cause dead spots of algae and some sponges on LR can be killed by air bubbles as well.

 

[alrmc4]

i have been messing with my flow for over 6 weeks now when the flow is turned up high i get the bubbles could be what dogofwar mentioned when the flow is turned down the over flow makes a horrible racket trying to find the happy medium if there is one...