Pual, every time I squint at your picture and move my head side to side, I start to see visions of SuperModels. Am I doing something wrong?
I start to see visions of SuperModels. Am I doing something wrong?
Yes he does. He told me so. But not for the same reasons DSBs crash or don't last long or whatever the problems are. Me, or "he" has to create typhoons because he, or "me" uses a reverse UG filter which utilizes gravel. The "cleaning" is to ensure the gravel does not clog as I need circulation throughout the entire bed. My system depends on some detritus to slow down the water flow and create areas where bacteria (and pods) will feel welcome. I don't think of detritus as a bad thing, just an inert substance that tends to clog my RUGF.
Sorry for the intrusion. Please continue with your fascinating discussion. :wave:
Paul uses dolomite, rugf's don't work on little particlesPaul is your tank's substrate aragonite? How coarse would say it is, mm size particles?
So where does nitrate fit into all this? Nitrates are an electron acceptor used during respiration of carbon compounds in low oxygen environments. The nitrogen in nitrates are used in place of the more energetically favorable oxygen. What happens is that electrons freed during breaking of carbon bonds plus hydrogen combine with oxygen and nitrogen atoms of the nitrate molecule to form N2 and H2O. (See Denitrification).
Why does that work better in a Bucket DSB compared to in the rest of the tank? The conversion of ammonia to nitrate occurs on every surface of the tank. In a Bucket DSB, the bacteria responsible for converting ammonia into nitrate are now in close proximity to the bacteria that are using the nitrates for anoxic respiration. , the nitrates have just as likely a chance of diffusing up out of the top of the sand as it does down to where the bacteria are actively converting it into nitrogen gas.
How is this different from inside the display?In the display, the nitrates released by the bacteria gets released into the water column and therefore is readily accessible to the algae for growth. By contrast, any nitrates that travel lower into the sand bed will be broken down and released into the air and can no longer contribute to biomass growth.
Whether the substrate is in the bucket or at the bottom of the aquarium, the statement "ammonia is oxidized on all surfaces" can be true for both systems. Also, I am not aware of any evidence that substrate in a bucket is any more effective than the bottom of the tank. The fact it can be changed out much more easily than substrate in the display tank is a plus.
I think this might be a mistake. The fluid dynamics around substrate in a bucket and the display tank do not to seem to be all that different. Why would substate in the tank spew out nitrates and wouldn't in a bucket.
The two quoted points are unnecessary to explain the success of substrate in a bucket biofilters.
The difference is depth. The bacteria all over the tank are oxidizing ammonia. The bacteria in the sand are just as effective as those say on the glass or on the rock. The difference is that the bacteria in the bucket are close to other bacteria in a lower oxygen environment. That proximity means that some of the nitrates are migrating towards that anoxic environment instead of just getting released into the tank. Not all, but enough.
Actually, it does. The difference is that nitrates diffusing down in the display run into the bottom of the tank, nitrates diffusing down in the bucket are consumed by the bacteria in the anoxic zone at the very bottom of the bucket.
BTW, the reasons UGFs were first implemented in aquariums was for nitrification of ammonia. Bioballs serve the same function. The issue we run into is that both of these filters halt the nitrogen cycle at nitrates. By contrast, a Bucket DSB is able to close that cycle and convert the nitrates into nitrogen gas which then escapes the tank.