A curtain of bubbles instead of one noisy stream.
A wide curtain of fine bubbles across the aquarium rather than one column. It looks better, it agitates more of the surface, and it is quieter than a single stone working hard.
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Size: 7 in / 17.8 cm
Why you'll love it
One stone makes a narrow column. A bar spread across the back lifts water along its whole length, which turns over the surface far more evenly and looks considerably better lit from behind.
Big bubbles surface with an audible plop. A diffusing strip breaks the same air into much smaller bubbles, which is the difference between a tank you notice in a quiet room and one you do not.
The bar has no motor. Bubble density is set entirely by the wattage of the air pump feeding it. A bar this long on an undersized pump will bubble from one end only.
Good fit if
Look elsewhere if
Gas exchange happens at the water surface, and what bubbles actually do is disturb it. A single stone in a corner disturbs one patch, so a wide tank ends up well agitated at one end and static at the other. Spreading the same air along a strip moves a much larger area of surface.
It is quieter as well, which is not obvious. The same volume of air through one small stone produces larger, faster bubbles bursting in one place; through a long strip it comes out as finer bubbles over a wide area, and the sound is a diffuse hiss rather than a concentrated churn.
At a centimetre in diameter it tucks behind background plants or a piece of hardscape, so what you see is the bubble curtain rather than the tube producing it. The moulded suction cups hold it to the back glass without any additional fixing, and the strip bends to follow a bowed or curved panel.
Match the length to the tank rather than buying the longest. A bar much shorter than the tank leaves the same dead ends you were trying to avoid, and one longer than the panel has to curl round at the ends, which restricts the flow at exactly the point it is bent.
A long bar needs more air than a single stone to produce an even curtain along its whole length, so a very small pump may only manage the near end. If you are running one alongside a sponge filter, check the pump has the capacity for both rather than assuming.
A flow valve on the line is worth adding either way. It lets you tune the density of the curtain, turn the noise down in the evening, and balance the bar against anything else running from the same pump without throttling the pump itself.
In the box
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The details
| Length | Suits | Notes |
|---|---|---|
| 17.8 cm | Nano and small tanks | Fits behind a small piece of hardscape |
| 25.4 cm | Standard 60 cm tanks | The usual choice for a community setup |
| 35.6 cm | Wide and long tanks | Needs a pump with enough output for the length |
Match the bar to the width of the panel it sits against. Too short leaves dead ends; too long has to bend round at the ends, which restricts flow exactly where it is kinked.
Bubble bars clog. Mineral deposits from hard water and biofilm both build up in the fine pores, and the symptom is bubbles from one end only. Pull the strip apart, rinse it thoroughly, and soak it in a weak vinegar solution to dissolve limescale if you are in a hard water area.
Rinse it very thoroughly afterwards and let it dry before refitting, since any acid residue should not go back into the tank. Every couple of months is a sensible interval, and a bar that no longer produces evenly after cleaning has reached the end of its life.
Loved by real pet parents
I had one stone in the corner making a narrow column and it looked like an afterthought. The 35.6 cm bar runs the width of the back and lit from behind it looks properly good. The suction cups are moulded in, so there is nothing extra to fit.
On my small single outlet pump the 35.6 cm version only bubbled from the end nearest the inlet. Moved it to the bigger pump and the whole length came alive. Worth thinking about before you pick a length.
The bar itself is fine and the bubbles are much finer than a stone gives. Mine is the 25.4 cm one and it came without a connector, which the description does say, but I had not registered it and had to dig one out of a drawer. Once connected it has been fine.
My tank has a bowed back wall and a rigid bar was never going to sit flat against it. This one follows the curve and the cups hold along the whole length. Being only a centimetre thick it hides behind the planting easily.
The old stone made a steady plopping at the surface that you could hear from the sofa. Fine bubbles off the strip break much more softly. Same pump, noticeably calmer room.
It ran beautifully until April, when one end started to splutter. It does pull apart for cleaning as described, and a soak sorted it, but getting it back together took more fiddling than I expected. Back to full length bubbles now.
I wanted some movement in a nano without turning it into a jacuzzi. The shortest length sits along the back of a very small tank and puts out a gentle line rather than a torrent. The cups have held since November.
Bought it mostly for the look and the children treat it as the main event of the evening. It sits behind the rocks so you see the bubbles and not the bar. Only a centimetre across, so it tucks away completely.
One stone was only turning over the corner it sat in and the far end always had a film on it. Spreading the same air along 25.4 cm lifts water across the whole back and the film has gone. Same pump, better distribution.
Good questions
The 14 inch does. The supplier has revised the 7 and 10 inch and they no longer ship with an accessory connector, so you may need a spare barb if your airline does not push straight on.
Almost always an underpowered pump. A long bar needs more air than a single stone; either shorten the run or fit a pump with more output.
Pull it apart and rinse in tank water. Limescale and biofilm block the pores over months, which shows up as patchy bubbling.
Check the listing, as the 7 and 10 inch versions no longer ship with one. A standard airline connector is inexpensive and worth having spare in any case.
The pores at the far end have clogged with limescale or biofilm, or the pump does not have the output for the length. Clean it first, and check the pump capacity if that does not fix it.
Pull it apart, rinse it, and soak in a weak vinegar solution to shift limescale. Rinse very thoroughly and dry it before it goes back in the tank.
Last reviewed 30 August 2026