How Often Should I Clean/Change the Filter Media

[Shaxx_on_a_Sax]

Hi everyone!

I just wanted to ask a question about filters and changing the media on them. I've read up a bit on the topic already, but I wanted a bit more clarification on whether or not I should change out the filter or just rinse it in tank water.

I have a fluval HOB filter with sponge, carbon, and ceramic components along with a sponge filter for my 40 gallon. Would I need to buy new carbon and sponges every month or so for the fluval, or is it ok to just rinse them out?
I'm not too worried about the sponge filter since most sources I've read said it'll be fine to rinse out occasionally, but the HOB I'm not too sure about because it has more moving parts and components to the filtration system.

 

[Murk]

Rinsing is plenty.
Only the carbon will, eventually, become saturated to the point that you can't rinse it out - for a regular tank this could easily take a year (or more). Bags of carbon are also dirt cheap and you don't need much.

For all else, rinsing will do.
Your filter serves basically three functions:
- To be a large surface area for beneficial bacteria to live on (hence all the holes and porous surface). You don't want to kill or flush away the bacteria, which is why you should indeed rinse in tank water.
- To catch off the larger bits of dirt. Rinsing these off is fine.
- And in the case of activated carbon, a little bit of chemical filtration.

As for how often: once you see a lot of sludge. It really depends on the tank.
Once you see a lot of sludge in the filter, give it a good rinse, put it back and you're good to go again!