Sponge filter question for 29 gallon tank

[Max Grubbins]

Hi everyone.  I have a 20 gallon long that has been running for 2 years on a medium co-op sponge filter.  I am considering moving up to a 29 gallon and I'm wondering if a single medium sponge will still be adequate.  Is anybody else running that setup or have any experience doing so?  I would like to avoid motorized pumps if possible.  Thanks.

[Ben P.]

I believe the best answer would be it depends on how many and what kind of fish you're putting in it

[Max Grubbins]

Not many. I have 7 danios, 2 amanos and a mystery snail who would all move to the new tank. I don't stock very heavily 

[Ben P.]

I would probably use the medium one then

[AllFishNoBrakes]

I have 2 29’s. One has a medium sponge filter with a Tetra Whisper 10i internal tiny filter. The other has a large sponge filter with a Tetra Whisper 10i internal tiny filter. Cartridges were thrown away and just some sponge shoved in the Tetra’s. 
 

Im confident either of them would be perfectly fine with just the sponge. I just like the little surface agitation and flow the little internal filters provide. 

[Max Grubbins]

I may look into those filters.  I've tried adding small internal filters and powerheads to increase flow in my 20L, but it never works out due to bad suction cups, rattling impellers, etc.

[nabokovfan87]

On 9/20/2023 at 5:02 PM, Max Grubbins said:

Hi everyone.  I have a 20 gallon long that has been running for 2 years on a medium co-op sponge filter.  I am considering moving up to a 29 gallon and I'm wondering if a single medium sponge will still be adequate.  Is anybody else running that setup or have any experience doing so?  I would like to avoid motorized pumps if possible.  Thanks.

If you're "doing fine" with that filter in a 20L then you're probably stocked pretty well.  If you plan to add more fish, then I would jump up to the largest size sponge you can. 

On 9/21/2023 at 3:45 PM, Max Grubbins said:

I may look into those filters.  I've tried adding small internal filters and powerheads to increase flow in my 20L, but it never works out due to bad suction cups, rattling impellers, etc.

Just add a ziss airstone on the tank, that helps a ton with movement in sponge/air setups.

Edited September 22, 2023 by nabokovfan87
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