Replacing Filter Media

[timmystood]

How come when you replace the filter media your tanks don't go into a new cycle - because surely by removing the filter media you are killing all the friendly bacteria!

I know there is some in the gravel etc. but I always thought most of it lived in the filter media?

 

[monkeyman]

IMHO id say it could depend on your size of tank and what kind of filter you have. It also obviously depends if you replace ALL the filter media & how many & what size of fish you have....

 

[Fella]

I alwsy ensure I don't have a full cycle by removing only one of many sponges. Replacing all of them at the same time would mean you'd get a cycle.

 

[IceH2O]

When I'd replace the media in my Penguin 170, which only has the 1 cartridge, I'd cut the blue felt off the old cartridge and put it in the bottom of the filter and then add the new cartridge. Then when it was time to replace the next cartridge I'd do the same and take out the 1st piece and replace it with that piece. Never had a problem as the bacteria was still there from the last cartridge.