NONE Oscars are really messy and grow up to a foot! They need at least 50 gallons. For a 10 gallon I recommend some guppies and neon tetras.
you can put a betta in a 5 gallon tank
one
you can put a betta in a 54 gallon tank
3
normal rule for fish in a tank is: For every 1 inch of fish there is 1 gallon of water
About three or four
No you should not 2 bearded dragons should be put in at least a 75 gallon tank. You could put them in a 55 gallon tank but they would be extremely stressed out.
either a 15 gallon tank or a 20 gallon tank
precisely 2.2
Fuel tank holds ( 18 gallons )
You can put it on a table if you choose. NEVER put a tank on the floor.
guppys are tropical fish. they require a heater, and 1 gallon is to small for a heater