Hydro sponge filter help

[MYDRAAL]

I'm even looking at the pictures and can't figure this thing out :rolleye1: I've connected the air line to the bulls eye but all I get is bubbles coming out at the top with or without the lift tube. There's holes surrounding the bulls eye right where you put the air line ???? How is the air pushed through the sponge with it being like that? BTW I'm just running an air pump not a powerhead. I know I'm going to kick myself when this is figured out but i want this running so any help will be appreciated

 

["Umm fish?"]

You aren't pushing air through the sponge. The air bubbles constantly push water up and out of the top of the lift tube. That pulls water in through the sponge to fill the void.

 

[MYDRAAL]

I don't get it. The air is coming in right at the top of the sponge and exiting right near where it's coming in at ???? Do I have it set up wrong? What's the point of the lift tube, to keep the bubbles inside the tube??? I have to be doing something wrong this doesn't make sense.

 

[billsreef]

It should end up looking like this, with the airline going down the middle of the lift tube and attaching to the "bullseye"

The bubbles rising in the lift tube push water up the tube. This causes a current of water coming in through the sponge and going up the lift tube via being pushed by the bubbles. The only purpose the air serves is to pump water

 

[MYDRAAL]

Ok, now I think I get it. As the bubbles escape it lightly pulls water with it. So I should still run an airstone somewhere else in the tank right? This doesn't seem like it would add enough oxygen to the water column.

 

[billsreef]

Yup, your getting it now Even when just using an air stone for oxygenating the water, it's not the air bubbles themselves adding O2 to the water, but rather the circulation caused by the air bubbles pushing the water around that allows the water to pick up O2 at the surface of the aquarium. The small size of the bubbles and short contact time prevent the bubbles themselves from adding any significant amount of O2. So all we do with air is actually use it as a water pump instead of using some kind of impeller driven water pump Just think of your air bubbles as a low tech powerhead

 

[MYDRAAL]

Got it:thumbsup: Thanks for the help guys