well then allow me to "educate" you
Beneficial bacteria will grow on ANY available surface in your tank if you dont have a proper filter, or no filter at all. Regardless if you have a plastic plate under your substrate, bacteria will grow there if it does not have a more suitable place to grow (like the bio-media of a proper filter). the amount of "flow" through a UGF is marginal, and nearly unmeasurable, while a proper filter will give you a much higher flow rate resulting in much better mechanical and biological filtration. even in highly overfiltered tanks, we do not come anywhere near the flow rates that hinder the nitrogen cycle. so, why use a UGF that traps all the crud IN the tank, and has almost 0 flow rate, when you can purchase a proper filter?
UGF do nothing more than trap debris and detrius under the plates, making it near impossible to clean thoroughly without completely disassembling your tank.
you are just as well off using NO filter, as you would be using a UGF. if you dont have a canister or HOB with proper flow and bio-media, bacteria will look to colonize anywhere they can. this usually happens in the gravel, and on porous surfaces in decor. so even if you are using nothing more than an air stone/ air pump (no UGF plate, and no other filtration), the bacteria will grow in your substrate just the same, first colonizing closest to the stone, as it would be the best available space.
as far as surface area, i think you, like most other novice keepers, have a crude misunderstanding of bacteria colonization.
your system (display/filter/etc) will
only house as much beneficial bacteria as is needed. this is solely dependent on the amount of available ammonia in the tank. in most wet/dry filters, sumps, and canisters, most of the biological media is not actually being used, and is simply taking up space.
because of all the rotting detrius under the UGF plates, the ammonia levels in the tank are much higher than they rightfully should be, so a larger surface area is needed. but without those plates trapping rotting debris, your available ammonia levels will be much lower, and the bacteria colonies will die down to the appropriate levels.
why do you think people run huge tanks using nothing more than a sponge filter?
and youre right. they were used for decades before canisters.
but then again, people used to write with rocks.
does that make it the best or most effective way to get the job done at present time? absolutely not.
there have been so many advancements over time that UGF have been rendered absolutely USELESS. they simply do more harm than good, and there are much better products out there, even on a low consumer level, that surpass this ancient system by leaps and bounds.
you cant argue with science. sorry.
