[coolseadra]

I'm setting up a 5 gallon tank for my Betta (Currently in a 2.5 gallon unfiltered)
I want to get him a Marina Power Filter, but the cartridges are $3 each and it seems like it'd build up pretty fast.
Are there any alternatives that I could use in place of a filter cartridge?

 

[Rose of sharon]

If you want to use a filter cartridge, you can. The company says to replace it monthly, but don't do that. You can clean it once a month or so by swishing it in dirty tank water, and that will save the beneficial bacteria. I am using the same filter cartridge in my filter that I started with over a year and a half ago.

If you want to look for something else to use, there are things like cut to fit filter material and polishing pads. There are even small balls or bio rings that you can use, as long as they can fit into the filter.

I have a hang on back filter that has a filter cartridge, some cut to fit filter pad and a piece of polishing pad all stuffed in there. I also have an intake sponge fitted over the intake valve. That is very useful. Betta's delicate fins can get sucked into an intake valve, so it's best to get a sponge that will fit over the intake to avoid any harm to the betta. And it also will build up some beneficial bacteria, too.

Hope this helps!

 

[imaal]

Yes, as @Rose of sharon stated there is no need to replace filter cartidges. The manufacturers tell you to in order to sell more of them. Just rinse them out in aquarium water. i have some that are many years old. Some so old I've lost track of exactly how old. I keep them til they start falling apart.