SPONGE FILTERS: Why and How

[Hallyx]

Putting a a piece of open cell filter sponge at the surface to catch the bubbles cuts down on surface turbulence.

Using an airstone on the bottom of your airfeed tube creates smaller bubbles and more of them. This cuts turbulence and is also more efficient,

[shawnee]

sticky

[Chevko]

Fantastic little gem of information! I do hope they they make this a sticky as this is has awesome information, plus the images on the original post gives an idea as to what to look for for filters. One website I was peeking through I wasn't sure what kind of sponge filter to get and almost just totally ignored them altogether. Good thing I haven't bought one yet!

[waterdog]

I guess my article wasn't deemed worthy of becoming a sticky.

I just want to thank everyone that voted for it to be a sticky and for all the great comments! I had fun talking about it.

[breezywillow]

Thinking about doing a DIY for my 2 gal tank, doing 2-50% and 1-100% water changes a week, what should I cut down to if I have a sponge filter or should I keep the water changes the same and just clean the sponge once a month?

[waterdog]

In my 2.5 with a sponge filter I simply do one 50% change a week and have no problems at all!

[breezywillow]

Thanks waterdog, your post was recommended by another member and has been really helpful in deciding on a DIY sponge filter, I agree with everyone else, this SHOULD be a sticky!!!

[logisticsguy]

Originally Posted by waterdog

In my 2.5 with a sponge filter I simply do one 50% change a week and have no problems at all!

We did a complete change from HOB to sponge filters last year on all tanks less than 10g. It was getting ridiculous the flow issues and breakdowns from the small HOBs. On larger tanks its good to have one of each in the tank as they can back each other up. The older the sponge the better and using the big tank to season up new sponge filters work well IME. Also a nice little trick is to take a pill bottle, fill it with media like Seachem Matrix, poke a couple holes in it and find a spot in the tank for it like inside a decoration or even attaching java moss to the bottle. It becomes an ammonia buster and can help keep a cycle stable.

[waterdog]

Originally Posted by logisticsguy

Also a nice little trick is to take a pill bottle, fill it with media like Seachem Matrix, poke a couple holes in it and find a spot in the tank for it like inside a decoration or even attaching java moss to the bottle. It becomes an ammonia buster and can help keep a cycle stable.

I like that idea!

[Sparrowhawk]

I agree that this should be a sticky! Wonderful thread!


A quick question though. I ordered a few sponge filters online (they were a couple of bucks each, less than the sponges at the cheapo store, haha!) and ordered two different sizes because I wasn't sure which would be best (the measurements were vague, it was eBay after all). Now they've arrived, one kind is teeny tiny, the other is massive in comparison to my 3.9gal tanks! Which of these would you recommend for a tank of that size (which will decrease in capacity slightly with the addition of gravel and more plants/hardscape)?

Small: 2.25" x 2"
Medium: 3.5" x 4.5"

That's not including the weighted bases and tube, just the sponge measurements. If I were to use the larger one, I'd have to saw some of the tube off, and sand it down smooth for it to fit under the water surface...

I wouldn't want to not have a large enough unit in the tank, it'd defeat the purpose of having one in the first place, but wow, is the "medium" big for where it'd be going! Heh.