eeekk my filter died what should i do/buy??

I would probably get a Wisper 5-15. They come with a start out cartridge and there only about $15. I have one on my goldfish tank, works great. It's a HOB filter, but it does the same hting as a normal whisper, but their smaller. The cartridges that you buy extra for replacements are the size "jounior"
 
I would take Harry's advice - a simple air pump powered filter will be your cheapeast option (given that you have the pump) and work very well in your size tank.

I know many others are tied to their HOB (whether its Aquaclears or penguin, etc) filters - but a breeder I buy fish from - who has over 150 tanks - has them all powered by simple air pump driven filters
 
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