Mercie

I have never had a Molly but a friend is giving me some. My question is can you keep a molly in a similar type of tank as a betta fish, i.e., small (1-5 gallons)? Can they be kept in goldfish type tanks without a filter or air bubbler (sorry, I'm sure there is a proper term for this). Thanks for any help you can give.

Gunnie

Welcome to Fishlore? The general rule (and I mean very general) is to have 1 inch per gallon of fish. This really is only a good guideline for smaller fish, but it can be helpful. One molly might be okay in a 5 gallon tank, but I wouldn't recommend it, simply because anything smaller than a 10 gallon tank is really hard to keep properly balanced. Bettas are a little easier to put in a smaller tank, because of their labyrinth organ which allows them to breathe oxygen from the surface. Since they can do this, they can survive in poorer water quality than other fish, but as a good fishkeeper, you wouldn't want to subject any fish to this. You would have to be really diligent in your water testing and water changes to keep the water quality up. It's doable, but not ideal. You will definately need a heater, a filter and the bubbler is for surface movement of the water so more oxygen is incorporated into the water. Even bettas should have filters in their tanks along with heaters.

Jason

I agree I see some pet stores here with bettas in like jars with nothing else or in very small parts of a tank. Its animal cruelty I tell you! Not saying your cruel as your tank is quite a lot bigger than the ones I'm talking about. Like half a gallon

Durbkat

Mercie you can not put mollies in with bettas they need to be in a 10 gallon tank or bigger. And they aren't tropical fish (fish like a betta) They are brackish fish (fish that need marine salt to live) So If you were going to take the mollies from your friend I would advise you to get a 10 gallon tank, let it cycle. Then ask your local fish store how to set up a tank for brackish fish (such as mollies) And they should tell you to get marine salt. Or they may tell you that they are freshwater fish (such as your betta), which they aren't. So tell them you need marine salt. But they can live in a freshwater tank but will not live long (mabey they'll live 2 to 3 months at the most).

Jason

Aww I dont know mollies can adapt to just freshwater because these days they aren't taken from the wild they are bred in captivity and the fish shops etc dont put salt in their tanks. I dont think its a neccessity, but yeah I'd say they'd need a bigger tank.