Place with more bacterias

[torres]

So, alot people say that there is more bacteria on filter that gravel, some people say there is more bacteria in gravel than filter.
Whos right and whos wrong?

 

[Scouser]

The filter houses a vast amount of the BB due to an extremely large surface.

Gravel is the same, faceted edges and lots of nooks and crannies to house the BB.

It's almost impossible to tell which has more, what we do know that the BB is the filter is more in use, as water is passed through it to be filtered.


Guess I'm on the fence? Lol

 

[blert]

There is no, or very very little, water flow bringing nutrients and oxygen down into the substrate (unless you have an under gravel filter), but there is massive flow through the filter. The filter has more bacteria. Try this, if you dare... Totally replace the substrate, you should not really see any issues other than a nitrate spike from churning up the funk. Now go and replace ALL of your filter media and see what happens.

 

[jlk]

I think it also has to do with the set-up & maintenance of a tank. A bare-bottom tank will have all of its bb in the filter. A tank run with a UGF will have all of its bb in the gravel. I have even seen some natural set-ups with no filter and only a massive amount of plants as well as another extreme of 100% water changes daily and not bothering with cycling/bacteria. Generally speaking though, I have to agree with Blert and say that the majority of your bacteria are in your filter media.

 

[HN1]

Bacteria will exist primarily where there is the highest O2 saturation. That is typically in the filter media. The gravel will host a primary colony in a UGF or RUGF set up.

 

[jetajockey]

I think there should be a distinction made here. Bacteria is a big word, a HUGE word. There is bacteria everywhere, on nearly every surface of everything. In aquaria, there is beneficial bacteria literally clinging to every surface in the tank. Beneficial bacteria is another big word, so lets narrow it down even more. Nitrifying bacteria, the kind responsible for the ammonia => nitrite => nitrate portion of the nitrogen cycle, is aerobic, so by it's own nature it is present in the greatest numbers in an area where there is both a high level of o2 and constant food source.

This is why the biowheel is/was so popular, it's hard to beat that amount of oxygen exposure, and they figured out that they could build massive bacteria colonies on a biowheel surface.

In most cases, massive amounts of biomedia surface are not necessary, and as mentioned, a tank without much biomedia or power filtration will find other areas to build the biofilter.

Does that mean substrate is pointless? Not at all, it serves a purpose as well, and it can also serve to some degree of nitrification and moreso denitrification, so it is 'bacteria laden' as well.

 

[torres]

Good to know about that. Ive never seen a article about it, but this explains everything.
Thanks for who replied.