Tank Mates: The 5 Gallon

Q: LP Wrote,

I wanted to ask you if you might make a post about suitable tank mates for a betta, say in a 5-gal tank. I’m getting ready to take the plunge into a 5-gal for one of my bettas (once he’s healed) and will be getting… SOMETHING. But there is a lot of conflicting info out there.

A: The 5 gallon betta tank is one of the most popular starter tanks for betta enthusiasts. It’s large enough to cycle and comfortably hold a betta but it’s just small enough where it can be difficult to house any additional fish. People ask all the time what betta tank mates would be suitable in a small 5 gallon aquarium. First, I think it’s important to point out that while bettas are sometimes kept in uncycled tanks (that have not established anaerobic nitrifying bacteria) most other fish do require a fully cycled aquarium with a filter in order to sustain them safely. For that reason, I don’t recommend adding tank mates to your 5 gal if you have not cycled it first. To learn more about tank cycling please visit All About Water to learn more about water parameters and Tank Cycling: The Fishless Method to learn about how to cycle your aquarium. Let’s assume you’ve done your homework, have cycled your tank and are ready to add some other creatures to your betta’s home. Some good choices may include:

Apple Snails (1)
Ghost Shrimp (several) also called Glass shrimp
Otos (2)
Full grown neon tetras (4 – 5)- too big to be dinner

You will quickly max out your bioload in your 5 gal so choose only one type from the list above (maybe an apple snail and a few ghost shrimp) but not everything on the list. Also, consider that some of the fish like otos and neons are shoaling fish and prefer to be in groups. For their health, one lone fish is not recommended. Increasing the size of your tank will allow you to get a really great school together where you can observe their natural behavior best.

Always research the species before you by them so you have a good understanding of their needs. Apple snails and ghost shrimp for instance need water rich in calcium to support strong shell/exoskeletal growth.

It is also good to test your own tank water or have your local fish store test it for you. Otos do best in water with a very stable pH. They are sensitive to pH crashes and may not be suitable for water with a very low buffering capacity. (KH)

Give yourself a little time with your betta before you buy your tank mates to observe his personality. Some bettas are very aggressive and may do best in a tank without any other fish. It may not hurt to have a “plan B” in the back of your mind should you find your betta attacking his tank mates.

It is sensible to assume all new fish may harbor disease or parasites. Never add a new fish to a tank without quarantining him for at least 4 weeks in a separate aquarium. To learn more, visit the quarantine section on the Nippyfish.net Tankmates page. Animals that are not fish, like snails and shrimp don’t usually harbor diseases that are contagous to fish. Some folks may recommend you quarantine them too, but personally I don’t bother. I don’t know if this is prudent advice, but take it as you will.

Now that I’ve scared you with all the things to worry about regarding choosing a tank mate for your betta let me say that I don’t want it to discourage you. Choosing a fish to keep with your betta is a lot of fun and you will get endless enjoyment from watching them interact. It might even spark an interest in a species you didn’t previously realize you loved. Definitely give it a try but keep the recommendations above in the back of your mind as you consider the right tank mate. One other thing to remember is 10 gallons are the easiest tanks to find at garage sales and online auctions. They are readily available and often less expensive due to their prevalence. If you are ready for an upgrade 10 gallons can provide dozens more options then a 5 gal.

The fish that can live with bettas article is a good read for this subject also.