Replacing biological filter media

Hi. How often (if ever) should one replace the biological filter media in one's filter? And then I imagine one should do it in stages and not at once. I'm using sintered glass. Does it degrade over time? Possibly due to calcium carbonate deposits or something similar? I can't remember how long the bio-media has been in my filter - all I ever do is very occasionally give it a light rinse.

Cheers.

 

Personally I would not try replace as you run the danger causing ammonia spikes. Remember that the numbers of bacteria in the filtration lives in equilibrium with the food available. Changing the amount of food available, like adding a new fish, or removing some of the bacteria, will cause an imbalance. This will cause a spike in the ammonia levels until the bacteria colonies have time to grow to the correct numbers to restore the balance.

If you would like to change the bio media, do so slowly and gradually to ensure that the bacterial colonies have time to slowly adapt.

 

@JonathanS: If it comes to things like ceramic rings or seachem matrix or any other physical media that your bacteria reside in should not be replaced. But, I do replace the sponges/filter batting on a regular basis. I use the batting they use to line duvet covers so after 3 months of use it becomes impossible to clean so I just chuck them.