For Those Who Use A Diy Sponge Filter

[woodstock]

I got a couple of questions about using a sponge filter with a betta.

And one thing I wanted to clear up, isn't there a current with a sponge filter? Even if it's the smallest one?

Anyones, with a DIY sponge filter, if I'm making one for my divided 5 gal, how big a sponge should I use? And is it okay to go overboard? (Like a HUGE sponge? Just curious). And the sponge material ... how would I know if a sponge is okay to use?

Much appreciated, guys

 

[Chard56]

I got a couple of questions about using a sponge filter with a betta.

And one thing I wanted to clear up, isn't there a current with a sponge filter? Even if it's the smallest one?

Anyones, with a DIY sponge filter, if I'm making one for my divided 5 gal, how big a sponge should I use? And is it okay to go overboard? (Like a HUGE sponge? Just curious). And the sponge material ... how would I know if a sponge is okay to use?

Much appreciated, guys

I just Googled ("How to make a sponge filter"). There are lots of different ways and shapes and sizes and ways of determining if the sponge is right or will rot in your tank. I was wondering myself. Just Type that in and pick one.

 

[Tolak]

Open cell sponge, this is the sort that doesn't hold water. This means most household sponges are out. Many household sponges contain antibacterials, totally defeating the purpose of a bio filter, and often poisoning your fish.

Many cushion foams found at a craft or upholstery shops are open cell, you want the cheapest available foam, as this does not contain flame retardants.

 

[woodstock]

Okay, and for size, how will I know what size is suitable for a 5 gallon?

 

[Tolak]

I use a pretty much standard size sponge, cutting the pvc shorter for more shallow tanks. One this size works fine for a 5-10 gallon loaded with angel fry, I'm sure half the size would work well for a couple of bettas.

 

[woodstock]

And it wouldn't hurt to go more than that, would it?
And for the PVC (or any alternative) tube, how high/low should it go?

 

[Tolak]

No, it wouldn't hurt at all. I use that size sponge in everything up to a 20 gallon, a 29 if more lightly stocked. I use two or more in larger tanks.

I aim for no taller than about an inch below the water surface, on deeper tanks it can be considerably shorter, leaving several inches of water above the pvc.

 

[woodstock]

Thanks, much appreciated!! I'll be working on it this weekend, I'll post pics if all goes well.

 

[woodstock]

Ah, another question actually - I've heard car sponges as recommendations. Do these not hold water?

 

[Tolak]

I've seen people use car sponges, they do hold water. Being closed cell they don't let water flow as well, offering less surface area for nitrifying bacteria to grow. The also seem to deteriorate quite a bit quicker. They will work, just not quite as well, and not as durable.

 

[woodstock]

I see, thank you.

 

[woodstock]

Alright I have another question regarding a sponge filter!!

I know it runs on an air pump. I just remembered that I used to use the Tetra Whisper 3i filter, and well...it has an airpump. I'd LIKE to use the airpump, however, it's stated to only go up to 3 gallons. Should I use it, or just buy another air pump? It will go into the 5 gal, divided.

And if I am recommended to buy another air pump, what would you recommend from an LFS and not online that is (and I stressssss this) pretty cheap?

 

[Tolak]

http/www.petsmart.com/product/index.jsp?productId=2752355#prodTab1

"Includes filter, UL-listed air pump (115V 60Hz 1.2-watts)"

I've found that watts, LPM and outlets pretty much coincide with larger pumps, no reason to think they wouldn't with smaller pumps. The pump you have puts out about 1LPM, and should be fine for a single sponge filter in a smaller tank. The smallest Tetra pump uses 1.5w, and is rated for up to a 10 gallon tank. I certainly would try it, as long as you have a gentle stream of bubbles the filter will work using that pump.

 

[woodstock]

LPM - liters per minute? Don't laugh if I'm wrong, haha

Alright, mathematically it should work (i solved using proportions), unless there's a technically more correct formula with this. So, why would the pump say it only goes up to 3 gallons? And for gentle stream of bubbles, could you clarify that? I have never used an airpump with an airstone before, so I have no prior experience how strong or weak bubbbles will go.

Thank you very much.

 

[Tolak]

Yes, that is liter per minute. I don't use air stones with my sponge filters, I just stick the air line down in there. A bubble or two per second is pretty gentile, this works well for bettas.

The 3 gallon size probably refers to the filter being run by the pump.