# Fluval 304 air bubbles



## Darkblade48 (Jan 4, 2008)

As far as I know, the Fluval 304 is not designed for wet/dry. More likely, there is some air that is trapped inside the filter, resulting in it spitting out bubbles.

If you rock the filter back and forth, it should help dislodge some of the air that is trapped inside.

As for slowing down the flow, I am unsure, but you could try putting a sponge in front of the spray bar.


----------



## shane3fan (Nov 2, 2009)

For slowing the flow, if it isnt already equipped, you could plumb in a ball valve and partially close it. 

Did you recently connect the filter? I have a 205 and when it is first connected it has a few bubbles from time to time--they go away on their own after a bit. I would consider that to be perfectly normal. If it has been running for more than a couple of hours I would not consider it normal.


----------



## Bees (Jan 6, 2010)

Thirded. Every time I clean my 304 it has a lot of air trapped in the lid. Rock it back and forth and forward and back as mentioned by Darkblade and that should alleviate the problem.


----------



## Jeff5614 (Dec 29, 2005)

Flow can be controlled by adjusting the aquastop, that's why it's there.


----------



## bcdudley (Nov 18, 2009)

I will check for air bubbles again tonight. It was just moved last night so that is a good possibility.



> Flow can be controlled by adjusting the aquastop, that's why it's there.


How does the aquastop control flow? I thought it was just for disconnecting the hoses. Looking at the instructions seems to confirm this.


----------



## Jeff5614 (Dec 29, 2005)

...The Aqua-Stop makes maintenance easy by stopping the water flow, permitting you to separate the hose assembly from the filter in one convenient step. It can be safely used to regulate water flow, without harming the motor or its components...

This is from the online manual, bottom of page 4, which I have linked below. The Aquastop, aside from disconnecting the tubing from the filter is also basically a ball valve. As you may or may not have noticed, there are two "handles" as we call them in east Tennessee. The bottom one completely disconnects the the aquastop from the canister. The one above that you can use to regulate flow. As you lift up it begins to close the valve decreasing flow.

http://www.hagen.com/pdf/aquatic/Fluval_Manual_082002.pdf


----------



## bcdudley (Nov 18, 2009)

I did not notice a second handle. I will look again. Thanks.


----------



## bcdudley (Nov 18, 2009)

Ah, looking at the picture on the front of the manual, I see the problem. My flow control handle is broken off. I got it used in a trade so no big deal. I may order a replacement. I need to order one of the side locking clips anyway.

Thanks.


----------



## FSM (Jan 13, 2009)

Air is trapped in it or air is getting sucked into the intake.

Reducing the flow is just going to cause it to take longer to purge all the air.


----------



## GTR (May 27, 2009)

I'm not at all familiar with the Fluval but since I noticed you'll be ordering other parts you might want to check all the replaceable seals you might need in the future.

SteveU


----------



## Juicy19 (Mar 3, 2009)

bcdudley said:


> Ah, looking at the picture on the front of the manual, I see the problem. My flow control handle is broken off. I got it used in a trade so no big deal. I may order a replacement. I need to order one of the side locking clips anyway.
> 
> Thanks.


if one of the side locking clips isn't functioning property, you're either going to have a leak or be sucking in air from "outside" the filter.


----------



## bcdudley (Nov 18, 2009)

There is a tie down strap wrapped around the outside holding it very tightly closed. I already found out what happens without it (outside of course). With the power running it was fine. As soon as the power shutoff, the top popped off the canister and it quickly emptied out the contents of the bucket of water I was testing with all over the ground.

The air bubbles did eventually stop.


----------



## FSM (Jan 13, 2009)

A canister isn't going to suck air in if it's got a leak. The contents are under pressure, forcing the water out, not drawing water in.


----------



## bigboij (Jul 24, 2009)

FSM said:


> A canister isn't going to suck air in if it's got a leak. The contents are under pressure, forcing the water out, not drawing water in.


^^ not really

i found the same when i had a seal tear on a quick release on my canister the bubbles shooting out every now and then is what made me think i had a leak, the canister was driping water but just like if you empty a 2l bottle it burps as it sucks in air.


----------

