615,142 gallons of water are needed to fill this cylinder.
To fill this pool to the very top you'll need about 1,480 gallons of water - less if you do not fill it all the way up.
Assuming the only thing in the aquarium is water, this tank could hold up to 19.8 gallons of water.
72 gallons is needed to fill the tank.
This can not be answered with the information you have given.
Three feet of water in a 12-foot round pool is about 2,550 gallons.
16 and 7/8
The volume of the pool is 2,290.2 cu ft and has a maximum capacity of 17,133.2 gallons of water.
About 18,000 gallons.