Switching to a sponge filter

[OhioFishKeeper]

I'm thinking about switching my filtration on a 2.5 gallon tank from undergravel to sponge. Would I just drop the sponge filter in there and operate it in unison with the undergravel for a month or so? Slowly start reducing the airflow through the undergravel riser?

To keep my pH under control, I assume I just need to have gravel that includes calcium...crushed coral. Mix is a 1/4 pound.

 

[Frank the Fish guy]

Yeah, run them both for a month to seed the sponge. Then you can just turn off the UGF.

All tanks really should have some calcium carbonate in them. If the pH drops below 7.0 the calcium carbonate starts to dissolve into the water to raise pH back to 7.0. Nature's regulator.

 

[KingOscar]

I'm curious as to why you would do this. A 2.5 is so small and doesn't need a sponge taking up precious space. Many years ago (decades, actually) I ran a 2.5 with UGF and a Betta. It worked well.. the fish was content and lived several years.

What do you have living in this tank?

 

[SparkyJones]

Aquaneat makes a nano sponge filter right around $5-6 with a corner design that takes up a little less real estate in the tank than round sponge filters do.

If you could run them both, you'd have the UG for dominant biological and the sponge for dominant mechanical filtration, and cleaning one or the other doesn't disturb the cycle much as long as it's done at different times like a week or so apart.
If you run 2 uplift tubes normally in the corners, you could cap one at the plate and just run it on the one uplift and a sponge on the other side and this might get you the filtration you are looking for. could probably modify that corner sponge filter to sit around a single uplift tube to get a little more real estate in the tank also.

Not sure of the problem you are trying to correct by doing this.. Maybe fine particulates in the water that don't settle? if so, you need a fine, not a coarse sponge to capture them. Most folks would just buy a really cheap small HOB, put a cotton filter pad in it and put it on the tank for an hour or two and take it back off afterwards to clear the water of particulates when needed, if needed, it's a small tank, shouldn't take much or a long time if that's the issue.

 

[OhioFishKeeper]

Thanks for the responses. I think it will be easier to clean the sponge filter. I'm seeing some build up in the gravel currently and I have this green spot algae forming below the level of the gravel. If I didn't have such deep gravel, it would be easier to get rid of the algae. The deep gravel is also taking up water space.

 

[WRWAquarium]

What about a really small HOB filter?

 

[OhioFishKeeper]

What about a really small HOB filter?

I thought about that, but I have a Betta and I hear they don't do well with water movement.