What fish can I put in a 5 gallon that already has a Betta fish?

The tank is not empty, you had two Betta's in a 5 gallon tank, which gives them 2.5 gallons each. Betta's need a minimum of 4-5 gallons each, or else they will not thrive. They need heated, filtered, and cycled water, with live plants in it to thrive. Please consider this when thinking of fish, the only fish that live in a 2.5 gallon tank is one ghost shrimp. Your Betta will do fine by herself. Good luck!

You are correct, you can keep other fish with a betta, but it's much easier in a larger tank. Most fish that will live happily with a betta are social or schooling fish (White clouds, Neons, cory cats etc) So you need space for the betta AND 5 or so other fish. In a 10gal or bigger thats easy, but in 5gal you are pushing things. You could try a few white cloud minnows or a couple of dwarf cory catfish if you are really keen and keep up the water changes etc. It does depend on the temperment of the betta too Ian

Fish his size or bigger is best (though harder to manage in a 5 gallon), without tail fins that he will try to grab. Neons are also a good pick because they are fast, and unless you purposely buy a long-finned tetra, they have short tails that aren't so much of a target. In a 5 gallon, I would only add 3 tetras (just enough to feel comfortable in a school). With the betta being territorial, you don't want to crowd "his" space with new fish, but enough to school is good for the tetra's protection.

A five gallon tank is perfect for the betta by himself. If you really want something else, get a snail and nothing more.

With Bettas, I've had more trouble with other fish picking on the betta than I've had trouble with the betta picking on them. I'd avoid most tetras and all barbs, as they tend to pick at the betta's long fins. Neon or cardinal tetras would be nice. So would White Clouds. A couple of cory cats would also be cool. I've had it work with guppies, but I've also had my betta picked on by guppies, so that may or may not work. I can't think of much else that is small enough for a 5 gallon tank. A 10 gallon tank would greatly expand your choices! :)

Betta's can be kept with several types of other fish, as long as no one in the tank has flowing fins and no other male betta's. Gourami's are on the line, some Betta's are ok with them, some want to fight with them. I have a half moon betta in a 6 gallon with some glow light tetras and some pygmy cory's and everyone. I also had a betta in a 50 gallon tall tank with a full community. He never bother anyone and the only one that bothered him was my school of tiger barbs. But This all depends on the betta because I have a betta in a 3 gallon that won't live with anyone, he even attacks snails. Try out some tetras and Cory's, my recommendation, good luck

i had one with guppies in with, the little neon fishes, small cat fish, i had the little angle fish also with mine,anything small and non aggressive, start with only 2 or 3

Ghost shrimp aren't really fish but they're really cool.

i have had plecostomus with the betta. they leave each other alone. and the pleco cleans the tank! the betta tend to go after other fish with flashy colors or longer tails. i have had several betta in a tank together though, and if they are well fed they don't even mess with each other. i sed to go to the pet store and get a little frozen bag of shrimp. but they are really tiny, just looks like frozen brown ice, break off a little piece and put in tank, then you see it separate into little shrimpies. it is good for the betta and helps with the hunting instinct. and then they don't need to eat other fish.