When should I change carbon filter?

[Jestocker]

20 gallon tank, just finished cycling a few days ago.
3 black Molly swordtail fish, approximate 2 months old.

I looked at the other filters in the pump and they have growth on them, do I leave that alone?

Would also like to add a bottom feeding fish, any suggestions? I read a plecostomus (spelling) was not a good idea as it might eat some still relatively small fish.

 

[j2112j]

20 gallon tank, just finished cycling a few days ago.
3 black Molly swordtail fish, approximate 2 months old.

I looked at the other filters in the pump and they have growth on them, do I leave that alone?

Would also like to add a bottom feeding fish, any suggestions? I read a plecostomus (spelling) was not a good idea as it might eat some still relatively small fish.

Hi Jestocker,

I rinse my filter media in old aquarium water, every other water change.

Seems many people don't use carbon unless they need to get rid of a nasty aquarium smell, or if they need to filter any excess medications in the water.

Many people us a filter floss or extra sponge in the filter, instead of carbon. If you plan on using carbn, it loses it's effectiveness between 2 to 4 weeks, roughly.

I don't like pleco's myself but you may want to research the bristlenose pleco. Not sure if they are appropriate for a 20 gallon tank, but many people like them.

 

[Rosenweiss]

Definitely don't replace any filter media, you'll have another mini-cycle! You can rinse your media in old PWC water, but make sure to rinse it one piece at a time, waiting a week between, so not to lose too much bacteria.

A small pleco is quite suitable for your 20g, I'd get a clown pleco, or a bristlenose, or another species that does not exceed 5". It will not eat your fishies.

 

[melosu58]

Moving this to the FW General discussion forum. More people will see it there.