Bioball debate

Everything everyone has said here is correct, but keep in mind vitreous surfaces limit the types of bacteria and the types of reactions that will occur.

 

Wow, thanks all for the info so my understanding is bioballs are more of an insurance if properly maintained? Also, if I decided later on to have corals, which is becoming more likely it would be beneficial to have bioballs or some other bio filtration in the sump? Not only that but my husband and I favor carnivores so added area for bio filtration is good, yes?

 

My simplest thoughts on the matter are that the bio-balls with the surface area, are extremely efficient at the ammonia to nitrite and nitrite to nitrate. However, the the bio-ball material doesn't not allow water to reach into it's depth where anaerobic bacteria could convert the nitrate to nitrogen gas to be "offed".
The live rock, with it's pourosity, gives for excellent stages to produce the nitrate, but also, it still allows nitrate laden water to permeate the depths of the rock where the anaerobic bactiera are able to process the nitrates.

 

Hopefully Steve Wright will chime in here.He once showed me some data that denitrification is not only occuring in the anaerobic zones but also in the aerobic areas as well..

 

The problem with bioballs is not necessarily detritus (as mentioned but not fully elaborated on). This may contribute to some extent thoug. A concept that is pretty basic to microbiologists though, but apparently not as common a concept for hobbyists to conceptualize. this is the idea of proximity associations. As mentioned, bacteria form mats, and species of bacteria that benefit from by products of other bacteria, will tend to grow near this "other" bacteria.

So, bacteria that can "denitrify", will tend to grow near bacteria that will "nitrify". This way there is an efficient transport of nitrate from point a to point b. with bioballs, the O2 level s too high, so, you get lots of nitrate, but there is no bacteria in close proximity to utilize it. Once it spreads out all over the tank, the the efficiency of utilization be denitrifying backeria should decrease as it is not constantly coming into contact with bacteria in low oxygen surfaces and therefore there is a potential for N to increase. If the N is produced right next to denitrifiers, on the other hand, the correct bacteria is right there and ready to convert to insert nitrogen gas, so if the system has what it needs to work efficiently, there is less chance of accumulation.

It's a pretty simple concept I think, but the internet is littered with talk of detritus buildup, so, that is what hobbyists will talk about. Detritus builds up anywhere there is sufficient flow though, this isn't unique to bioballs, it can occur in substrate, live rock, protein skimmers, plumbing etc... What is unique to bioballs is the high O2 ratio and therefore lack of any denitrifying bacteria.

 

Well I,m not Steve, but I can point to data pretty readily . You'll probably never get denitrification on bio balls though due to high O2, but likely would get some on other surfaces, such as live rock, sand even aquarium glass probably

See:
http://www.cs.montana.edu/webworks/...pters/chapter010/section003/blue/page001.html

 

I believe that there is nitrate removal going on before the depths of the live rock and the oxygen content in the water decreases somewhat, but is still present a bit but is in porous areas not readily getting water replaced with oxygen laden new water.
With the bio-balls, it has nothing to keep the oxygen water to access the surfaces of the bio-balls.

 

So in my AIO aquarium would it be logical to replace my bioball with coral rubble and some chaeto? I remember hearing about someone doing that.

 

Even if the balls are completely submerged under water?

 

The idea, of using bioballs is usually that tricking water over them allows for better gas exchange and more O2. The nitrifying bacteria can then, due to the increased O2, metabolize ammonia and nitrite into nitrate more effectively. However the problem is the will be too much O2 for denitrification to occur in close proximity. If the bioballs are fully submerged then the O2 would probably be similar to the rest of the tank (depending on placement for example), but then they are not "nitrifying" more efficiently than the aquarium glass, so what's the point? In that case, the I would agree they do little more than provide extra space for detritus accumulation.