Yes
Its completely up to the owner of the aquarium.
Yes if you keep a shark in an aquarium it will not grow to its normal size. It will only grow to a size that it will be comfortable in the aquarium.
They can just live in an aquarium with the normal pebbles on the bottom that all fish live in.
The name of bacteria which normal inhabit the body are called normal flora. The list of these bacteria is quite lengthy. Is there a system in the body in which you are looking for the normal flora names?
There is no "correct time". I would suspect that their lifetime would be many years. The media rings should only be replaced if they are decomposing or are totally blocked and have lost all their ability to house the bacteria that forms as and where they are supposed to. The normal thing to do is to wash about 3/4ths of them well and then only rinse the other 1/4 before putting them back to work in the filter thereby keeping the cycled bacteria alive and working.
I saw a dolphin at an aquarium, I wonder if this is normal behavior?
No. Normal urine should be sterile.
bacteria
many however they arent considered to be bad bacteria, its normal bacteria as is in yogurt and milk
Normal flora is more difficult to remove than transient bacteria. Normal flora are naturally occurring bacteria that have established a stable population on the body's surfaces, making them more resilient to removal efforts. Transient bacteria, on the other hand, are temporary and easier to remove through basic hygiene practices.
bacteria, fungi, virus, etc. pretty much the same as normal names
well no, wheat bread does not have any bacteria in it. It is just normal bread.