Microbubbles

[azzah]

I have a 6x2x2 tank with a 4 foot sump the water is pretty much crystal clear except that I'm getting lots of micro bubbles coming from my spray bar which is making it look dirty and it is really starting to annoy me. How can air be getting in when the pump in my sump is completely submersed and is 6 inches below the water line.

[Old Dave]

How can air be getting in when the pump in my sump is completely submersed and is 6 inches below the water line.

JMO, but if air was entering ito the system it would need to be before the pump or after the drop into the tank.

I would have thought that the latter would create bubbles, but not microbubbles.

If it was post pump you would have something called a LEAK!

When did the problem start? Is there already a lot of air in the tank?

Do you have another source of bubbles nearbly (airstone etc)?

Pearling?

I know you need as much air/water mixing as possible in the sump, so is it possible to put a "soft baffle" before the pump?

Is it possible to lower the spray bar a little more, or change the direction?

Good Luck, HTH,

Old Dave

[azzah]

How can air be getting in when the pump in my sump is completely submersed and is 6 inches below the water line.

JMO, but if air was entering ito the system it would need to be before the pump or after the drop into the tank.

I would have thought that the latter would create bubbles, but not microbubbles.

If it was post pump you would have something called a LEAK!

When did the problem start? Is there already a lot of air in the tank?

Do you have another source of bubbles nearbly (airstone etc)?

Pearling?

I know you need as much air/water mixing as possible in the sump, so is it possible to put a "soft baffle" before the pump?

Is it possible to lower the spray bar a little more, or change the direction?

Good Luck, HTH,

Old Dave

I can't remember when it started but it has been happening for atleast a couple of months

I do have an airstone in the sump but turning it off doesn't seem to stop it. I have tried changing where the spray bar points the jets but doesn't seem to make a difference. I will try and change the height of the spray bar tonight.

Could it be the strength of the pump? my current pump is a Resun HOB3900 3500L/ph. Could there be an air pocket somewhere in my return pipe

[oakes]

I remember having this problem a few years ago not long after setting up a tank with sump. At first i thought they were tiny dirt particles but were actually microbubbles. I wish i could tell you where they came from but i still don't know. They seemed to originate as the water moved through the sump media but it was difficult to tell. It got to the point where i thought i would just have to put up with them or change to a canister, then after a month or so they started to disappear and haven't been a problem since. Weird.

[genetik_defekt]

why get rid of em, i think they make the tank look healthy. Especially after a good clean and settle. but just mho.

[mcloughlin2]

What I have trouble comprehending here is you seem to think these bubbles make the tank look dirty. Are talking about small clear air bubbles that are maybe 1mm in diameter?

I find it hard to believe of all things someone finds bubbles dirty. They are very beneficial to your tank in terms of making sure it is aerated. Without any form of bubbles in an aquarium your oxygen levels would quickly plumet.

My advice - forget the micro bubbles and go and by an actual airpump to put more in the tank.

[azzah]

What I have trouble comprehending here is you seem to think these bubbles make the tank look dirty. Are talking about small clear air bubbles that are maybe 1mm in diameter?

I find it hard to believe of all things someone finds bubbles dirty. They are very beneficial to your tank in terms of making sure it is aerated. Without any form of bubbles in an aquarium your oxygen levels would quickly plumet.

My advice - forget the micro bubbles and go and by an actual airpump to put more in the tank.

Bubbles do not put oxygen in the the water breaking of the surface does. I have a weir going into a sump which adds enough oxygen. When you have lots of 1mm bubbles it can affect the clarity of the tank

[oakes]

Just curious, how long has the tank/sump been operating & how long since cycled.

[electricyellowz]

I had that same problem with a canister filter and the reason was that air had gotton trapped into some of the sponges and it was being relaesed into the tank. All I did was squeeze the pads and they were gone. Could someting similar be happening to your tank?

[Reillin]

Is your return to the main tank over the water surface? Try submerging it. A spraybar return will create bubbles.

[azzah]

Just curious, how long has the tank/sump been operating & how long since cycled.

Tank has been operating for about 1.5 yrs but the sump is about 2 months old. My old sump was a bio ball sump but the new one is a 5 chamber sump. Most of the bio balls that were in my old sump were placed in my new sump for a couple of weeks until my new media got some good bacteria growing and some of the bio balls were moved to my weir to quiet down the noise of the water falling to the bulk head.

I had that same problem with a canister filter and the reason was that air had gotton trapped into some of the sponges and it was being relaesed into the tank. All I did was squeeze the pads and they were gone. Could someting similar be happening to your tank?

will try that, I do have a lot of sponges in my sump although the sponges are in the 2nd chamber of my sump and the water flows through 3 other chambers before returning to the tank so would have assumed that any air would have escaped as it moved through the next couple of chambers

Is your return to the main tank over the water surface? Try submerging it. A spraybar return will create bubbles.

I do have a spray bar but it is below the water line and the jets are pointing down

Guess I will just have to wait and see if they disappear over time

[CThompson]

Micro bubbles are so small they look like the "white" water you can pour from a jug after it has boiled. Bubbles this size can have negative impacts on your fish.

However, I expect what you have is just really really small bubbles.

There are two sources for these bubbles, 1) air getting into the filtration/pump system. If your pump is fully submerged, check all above water connections to make sure there is nothing loose. It is possible that with enough water flow air is sucked in without any water dropping out. With perhaps the aid of a torch try turning the pump on and off and try to see where the bubbles are in the tubing. If they are in existence immediately at the pump outlet, then; 2) I expect it is cavitation. This may be fixed with a good clean to the pumps propeller, or thinking along the lines that this propeller is damaged, your next step is replacing the propeller with a new one.

It is my understanding that bubble aerate the water by effectively increasing the tank’s footprint. That is, O2 exchange is at the contact between water and air interface. Each bubble has a surface area, add all those surface areas together and you get a bigger tank surface area/footprint. I also expect that bubble bursting at the surface in effect just for a microsecond also increase the tank’s surface area.

Craig