hey can anyone tell me the best way to change my filter media plz, should i put the new media in with the current ones so the bacteria will get on it quicker or wat? thanks.
The only reason for changing the actual filter media should be if it is totally falling apart, in which case yes, add the new media while the old media is still in place to 'seed' it with the bacteria.
If the old media is just dirty then a gentle rinse with the tank water from a water change will suffice. but remember that the brown 'gunk' is actually a good thing!