We have a used 10 gallon glass aquarium complete with rocks, statues, plants, a filter, and a plasyo- something or other... well, a bottom feeder or "sucker fish". He's big and very healthy. The tank has plenty of room for some other fish as well. If you've been wanting to start a fish tank or have a little one who would love to have their very own fish for Christmas, this would be a great starter- just add fish!