Bacteria Life Test

[thecoolguy]

was wondering if anyone knows the hard facts as to where bacteria lives?

of course, we all know that it will be in the filter media / gravel / driftwood / etc....but where is there the most?

for example - in an established tank (cycled and running for 3 months) - if you were to change out the filter media to completely new material - how much would the environment suffer? what kind of ammonia spike would you really experience?

would the bacteria living in the tank be enough to continue filtering the bio-load of the fish? (bacteria in the gravel / driftwood / etc.)

interested ears want to know.......why? bottom line question is whether or not it ever makes sense to completely, 100% change the filter media to absolutely new....

[Willyleigh]

I have no scientific evidence but when I set up my new aquarium with an established filter sponge my new tank still took a while to cycle, so the gravel must hold a lot of the tanks bacteria.

Also the tank which I removed the filter sponge from was fine, I didn't test its water but none of the fish suffered so the gravel/ plants, ornaments and glass musthave held enough bacteria to cope.

[Chrona]

The bacteria lives on anything that has a large surface area and some decent water flow (for oxygenation), ie driftwood, gravel, filter media, etc.

[Lady Hobbs]

I can only tell you of my own experiences. I have moved my tanks several times and each time replaced the decorations and gravel and replaced all water. If I had a slight spike, at all, it lasted no more than a day or two. Water never clouded, I just showed very slight ammonia reading for a day or two. Had I saved a bit of water may not have had even that but for lack of buckets, I just replaced it all.

I have changed out my filter media many times on both sides and on both filters with never a problem as well. Keep in mind, the tank has to be well cycled, however.

[cocoa_pleco]

some lives in the substrate, a good chunk lives in the filter media, and some will cling to rocks and plants.