# Sponge filter; need plastic tube?



## kclone (Nov 11, 2011)

Can you post a picture?


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## Diana (Jan 14, 2010)

Plastic tubing OVER the sponge? 

I have used plastic tubing inside the sponge, and then set a power head on top. The plastic tube is the same height as the sponge on top, but does not go all the way through to the bottom.


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## thelub (Jan 4, 2013)

I believe the end of the tube needs to be submerged to create the right flow for the filter to work properly.


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## Hmoobthor (Aug 15, 2011)

yes..use the tube..

that's why they have it...cut it if you have to


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## Soup12 (Nov 10, 2012)

What if I just take off the tube?


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## Bandit1200 (Dec 11, 2010)

If you take off the tube you won't have a sponge filter, only an airstone. Without the tube there is no lift. This is the same reason chimneys need to be a minimum height to work properly. You can trim it to be at your appoximate waterline. The taller the better as long as it is not too much higher than your waterline. If you aren't comfortable with a razor, you can get a small tube cutter from the hardware store.

I can't tell from that angle if the base is on top of the substrate, but you can push the base down into the substrate to lower the height of the tube. As long as the sponge is not below the level of the substrate you will still get the full surface of the sponge filtering water.


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## thelub (Jan 4, 2013)

^^ what he said. It needs the tube to create the lift to draw the water through the sponge and do the filtering.


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## Soup12 (Nov 10, 2012)

thelub said:


> ^^ what he said. It needs the tube to create the lift to draw the water through the sponge and do the filtering.


Ive seen many people on local fish community not use the plastic tubing... Bubbles still go up. Can anyone else verify if u have to have tubing to make sponge work properly.

Thanks


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## somewhatshocked (Aug 8, 2011)

Unless you're using a powerhead to pull water through a sponge, yes - you need a tube to create lift. 

Don't want to step on toes or derail but... Your shelving unit is not likely going to be able to handle those tanks adequately. The only wire racks that can support weight like that in the long term are reinforced - even the ones that claim to hold 2,000 pounds per shelf. (I use one) Weight also has to be evenly distributed, which requires plywood beneath the tanks. That plywood also supports the tanks themselves, as wiring isn't uniform across each shelf and extreme pressure can end up being placed on your tanks. May want to consider a more heavy-duty rack system.


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## Soup12 (Nov 10, 2012)

somewhatshocked said:


> Unless you're using a powerhead to pull water through a sponge, yes - you need a tube to create lift.
> 
> Don't want to step on toes or derail but... Your shelving unit is not likely going to be able to handle those tanks adequately. The only wire racks that can support weight like that in the long term are reinforced - even the ones that claim to hold 2,000 pounds per shelf. (I use one) Weight also has to be evenly distributed, which requires plywood beneath the tanks. That plywood also supports the tanks themselves, as wiring isn't uniform across each shelf and extreme pressure can end up being placed on your tanks. May want to consider a more heavy-duty rack system.


Kay i will use tubing just cut it down thanks!

I have plywood painted black about 1" thick that entire tank sits on  total weight on each shelve rack is around 350lbs with water filled. Should be more than good, thanks for the concern though.


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## somewhatshocked (Aug 8, 2011)

My point: evenly distribute that weight. Having some tanks on a rack like that with more water/weight than others on the same shelf/by different legs is risky.

Wasn't offering tips in a derogatory manner but from direct personal experience. 

Even with weight properly distributed, your shelves are going to bow, warp and change shape over time.


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## Soup12 (Nov 10, 2012)

somewhatshocked said:


> My point: evenly distribute that weight. Having some tanks on a rack like that with more water/weight than others on the same shelf/by different legs is risky.
> 
> Wasn't offering tips in a derogatory manner but from direct personal experience.
> 
> Even with weight properly distributed, your shelves are going to bow, warp and change shape over time.


No worries I didnt take in a derogatory way  Yeh I will even out the water for sure. Well it seems very stable, will keep you posted few months from now if its still going strong.


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## Dolfan (Apr 8, 2005)

You don't want to cut too much of the tubing as you will lose some of the "lift pressure" that is created by the tube. The more tube you cut off the less flow through you will have. I would maybe split the difference and cut some of the tube but raise the water level closer to the rim of the tank.


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## somewhatshocked (Aug 8, 2011)

So you don't have to sacrifice as much of the lift tube, maybe you could push the base all the way to the bottom of the tanks?


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## Soup12 (Nov 10, 2012)

Going to put base all the way at bottom, raise water to brim, and trim like an 1" off.
Thanks for input, will post pics


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## Soup12 (Nov 10, 2012)

Bandit1200 said:


> If you take off the tube you won't have a sponge filter, only an airstone. Without the tube there is no lift. This is the same reason chimneys need to be a minimum height to work properly. You can trim it to be at your appoximate waterline. The taller the better as long as it is not too much higher than your waterline. If you aren't comfortable with a razor, you can get a small tube cutter from the hardware store.
> 
> I can't tell from that angle if the base is on top of the substrate, but you can push the base down into the substrate to lower the height of the tube. As long as the sponge is not below the level of the substrate you will still get the full surface of the sponge filtering water.


Does the sponge work well if tubing sticks out of water slightly, but bubbles overflow into the water?

Or is it better to be about an 1'' lower than water line that way when water evaporates the sponge will still be effective (If I am gone on vacation).


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## lochaber (Jan 23, 2012)

Airstones generate current by creating a bunch of bubbles that float up, and in the process they 'drag' the water with them.

For the sponge filter to work, you need a current of water to flow through the sponge. (bringing O2, -NO2, -NH4 to the bacteria to be broken down). So for the filter to work as intended, the water has to flow into the central chamber through the sponge, and then up the tube. Basically the airstone pushes/pulls the water up the tube. If the tube is shorter then the water level, this water will exit the tube, and more water will be drawn up from the central chamber, and then in turn from the tank through the sponge.

If you have the top of the tube even with the water level and slightly above, the current will be greatly reduced (though, I have seen set ups where there was enough power to lift the water a small distance). If it's just bubbles oozing over, the only water leaving the tube (and coming in through the sponge) is limited to the film around the bubbles. If it is carrying water up through the tube, you should be able to visibly gauge the flow, and make an estimation about how much water is moving through the tube.

I hope that makes sense without being overly simple.


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