Good small aquarium pet?

Hermit crabs are great aquarium pets :)

While no animal is necessarily 'low-maintenance', these animals require some of the least amount of care as other reptiles. Medium sized crabs (ping pong ball sized) do best in aquariums at LEAST 10 gallons and you can get up to 3 to live comfortably in there (more is proffered as they get very lonely). But if you have a much bigger tank (50 is recommended minimum) you can get a JUMBO crab or two! (Softball sized-HUGE!)

Hermit crabs need 2 water bowls available (one with saltwater, one with freshwater. Purified only, tap water kills them) deep enough for them to bathe in but with a way to get out so they don't drown. They also need a supply of fresh foods. NOT store bought hermit crab feed. They get vary bored of eating the same thing so mix it up. Most every fruit and vegetable is good for them! Just give them you table scraps!

Lastly, some enrichment. Some stuff to climb on as they LOVE to climb!

Do some more research and you're set!

how about a frog? or two frogs for that matter? Amphibians are great generally.

reptiles are cool, lizards or snakes, although they are kept in a vivarium, which is slightly different.

if you buy a female lizard, I have no idea how to sex a lizard TBH, you could call Elizardbeth - it's just a thought.

It depends on how small the aquarium is. You could have a small snake (like a corn snake), ball python, spiders, leopard geckos, etc. But all of those aside from the spiders 10+ gallon aquariums.

a turtle is a cool pet to have and easy to care for, but I'm not sure about the legal requirements to adopt one.

No you don't want fish which contain mercury similar to the autism inducing vaccines that are on the market.

Try a dog

Snake, frogs, toads, lizards, tarantula, millipedes, pretty much any bug.

a lizard

fire salamander