Betta fish grow to be an average of 2 inches from head to the beginning of the tail.
No.
Yes a betta fish will grow back lost scales with time and clean water.
No
Yes all Betta fish have teeth. They are very small and using magni glass may help if you ever want to take a close up look at them. :)
Betta fish grow paler and less active when they are sick or old.
The average is 1.5 inches
a long time
it depends on how small the bowl is betta fish usually dont grow larger then 3 or 4 inches
A Betta Fish or Siamese Fighting Fish are only a few inches. The females grow to about 2.5" and males grow to 3".
A nine month old betta is already full grown, so yes.
Yes, but slowely.