Sure ... and undergravel filters are noiseless but high maintenance and require a gravel substrate.

The sponge filter I was talking about specifically was the one I referenced in an image above.

You can get other sponge filters that stick on the side of the tank and the air lift rises above the water but the sponges seem to be much smaller.

I got 2 of those air driven spong filters $19 for both the arived today . Same as url provided. I had to turn the air pump down as they were realy noisy . How do i know what the correct air flow rait is ?

Thanks for the warning about the foam. Will use the foam i got from work for thermal insulation behind the tank .

Where do i get the correct foam from and what should I ask for ?

See viewtopic.php?f=3&t=58840&p=633580&hilit=Poret+foam#p633580 and pm Likoma for details.

As long as you see bubbles it should work. I turn mine down as much as possible but you're not going to get too rapid a flow even if you leave it on full.

This is an unteresting implamentation of a HMF http://m.instructables.com/id/Introduct ... ilter-HMF/

Well, it is said you can never have too much filtration but perhaps adding bioballs etc might be just over the top! KISS works here.

If you are going to use a powerhead to pull the water thru the mat, it doesn't mean you can't drop back to a battery powered airlift if there is a power failure. Also too much curvature in the mat can compress the cells reducing flow.

I used the simplest design where I cut the mat to just a little more than the width of the tank, and squeezed it in. But I started with a tank already full of water. If I had to do it again, I might silicone in some glass rails to hold it in place but that would mean emptying the tank out.

Just so that I understand correct the correct proceedure . With the air driven filters one does not clean them ? And if one does then it would be a single squeeze a bucket of aquaium water to dislodge heavy dirt ?

They are supposed to last for years. If you want to "clean" you slap them against a parallel surface. Squeezing can damage the cell structure.

They are supposed to last for years. If you want to "clean" you slap them against a parallel surface. Squeezing can damage the cell structure.

Cheers will leave them be. :-)