well, in a 1 gallon, i put guppy fry, yes it sounds quite cruel, but when you have other livebearers that have more fry, anything works! i also just put some native snails and a few plant leaves in there to see if i get anything good. if you had a undergravel filter, you could put 2 endlers in there, has to be stocked with plants though. i've seen this set up in action! but i still wouldnt recommended. if i had a spare, i'd just use it as an algae collecter...
hehe, there is actually no real point in having any animals of sorts in a 1gallon tank at all, if you insist on having a 1 gallon tank i would reccomend putting in just plants and MAYBE a ghost shrimp or amano shrimp of sorts. If not i would reccomend moving to a bigger tank of 2.5 - 5gallons because 1 gallon is extremely small and not worth doing realy unless you aim for everything in it to look oversized, lol, this is my first time on this place in Ages....
1 gallon is just fine for a couple of small fish or a betta. They are a pain to clean, you have to clean them more often than a bigger tank, they're harder to maintain good water chemistry and temperature and you can't do a WHOLE lot with them...BUT assuming you take care of it; a 1G tank can be quite fun and cute.
Some fish stay SO SMALL that you dont want to put them in a larger tank because then you can't enjoy them. What were those teeny fish that Gomer got? Even my ember tetras get 'lost' in my 10G tank...although I dont think I would put them in a 1, I would certainly have no qualm moving them to a 3 or a 5.
Oh, and like eyrie mentioned...it works great as a holding tank for tiny fry. Probably wouldn't work as a growout tank...but to keep them until they're a few weeks old. Its easier for them to find food in a smaller area.
I love adf’s, they are the reason I joined the slippery slope of aquarium ownership.
I would not put even one in a 1g tank. I’ve had two in a 5g tank before and they produce so much poop that I had to monitor their health constantly and clean the tank daily to keep them them healthy. They can die very quickly and suddenly, even if you are vigilant. I moved them to a 30g tank, added a few more, added a few fish, and now it’s much less maintenance to keep everyone happy.
I know that the pet stores sell them as being able to be simply added to a community tank, but their proper care is much more complicated. I would always recommend that the water chemistry be set for their needs, and then add fish who are suited with to it.
P.S. They are very much social creatures, and I believe that having one by himself is somewhat cruel.