I'm also not sure what kind of puffer fish would be best, I would make sure it's one that won't eat your other fish and one that is easy to take care of. Do some research first and ask around at other pet stores to see what they think, do you have more pet stores in your area or in another town that you could ask? Personally I haven't seen one in any of our pet stores that have fish, they usually don't have the neat salt water exotic fishes, think it might be time for a trip to pet co and see what they have there. I love aquariums so I hope you can share yours with us once you get it completed with your fish! Good luck and hope you find the information you are seeking out.