Goldfish Tank Mates: What Other Fish You can Keep with Them?

There’s one thing that’s true about us goldfish folks:

We love ourselves some FISH!

It may be because we might have a suspicion that our goldfish is lonely and wants a friend, or simply because we want to add some interest to our goldfish tank by adding another species into the mix.

So I can’t count how many times I’ve heard:

“What fish can live with goldfish?”

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Good question.

If you want the short answer, here it is –


Goldfish should be kept with other goldfish only, no other kinds of fish.

They just aren’t compatible (and I am speaking from experience here).

Sorry to burst your bubble :/

But do you want to hear a more satisfying explanation?

Well read on for the 3 top reasons NOT to try this at home!

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1. Temperature: Goldfish Prefer Cooler Water than Most Other  Kinds of Fish

Tropical fish (such as Cichlids, loaches, tetras and others) need to live in temperatures that would be too toasty for goldfish.

Goldfish (slim-bodied ones anyway) prefer temps in the 70 to 80 degree F range with changes from season to season.


Tropicals don’t require periodic cold spells, which help goldfish to shed their excess fat. In fact, colder water may harm their health.

One party would end up compromised, so it just isn’t fair.

2. Aggression: Your Goldfish Can Get Picked on

There’s no doubt about it:

Getting picked on isn’t fun.

For goldfish, it can be very stressful.

Putting other types of fish in with your goldfish all too often leads to bullying or injury.  Your goldfish may end up spending its days hiding in terror from its persecutor.

For example:

Algae eaters (such as the plecostemos) are responsible for a large number of goldfish injuries on a regular basis, as their suction cup mouth can fix on the side of the goldfish and chew away at their tasty slime coat.

Want to know the worst part?

They typically do their dirty deeds when nobody is around to watch them.

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This leads goldfish owners to think their fish are sick when suddenly they wake up to a large red sore on their goldy’s side.

Koi are notoriously overbearing towards their smaller fancy cousins and should never be housed in the same tank with them.  They also get much, much larger than goldfish and do best in ponds.

If this happens in your tank, don’t blame the bully. The fish isn’t being mean – it is just doing what it naturally does.

Right now, if you have your goldfish in with them, get them out immediately.

You may have to find another home, or start up another tank (we’ll get to that later).

3. Your Other Fish May Get Digested by Your Goldfish

It’s a fact:

A goldfish will eat any fish that fits in its mouth.

So while it is still young your other fish may be okay…

… Until after another year or so, when the goldfish has doubled in size.

One day you might look in the tank and think your other fish went *poof* into thin air.

Since they do it with their own babies… they probably don’t think twice about turning their tank mate into sushi!

Bonus Reason: Goldfish Have Different Diet Requirements than other Species

It’s a fact that goldfish require a large amount of vegetable material to keep their digestive tract working correctly.


Too much of a high protein diet can lead to swim bladder troubles.

The other type of other fish you get will probably have much different nutritional requirements than your goldfish.

This brings us to the next question:

So What other Fish Do You Put with Your Goldfish?

The good news is, you don’t have to have one isolated little goldfish as the only inhabitant of your beautiful aquarium.

(That is, if it is large enough).

Goldfish are community fish and get along great with other goldfish the majority of the time under normal circumstances.  Some people think they even form bonds with each other as lifelong friends.

There are some things to keep in mind, which are:

1. The size of the fish

It isn’t a good idea in most cases to put really small or young goldfish in with a “Shamu” sized buddy.

One will end up getting all the food, and the other one going hungry – which can lead to malnourishment.

2. The breed of the goldfish

Goldfish come in such a wide variety of shapes and body modifications.

While goldfish are usually peaceful, not all breeds are necessarily a good fit.

Some have very sensitive eye areas and may be more prone to getting picked on by more hardy companions – such as the Ryukin or Comet.

Make sure to research before even mixing different breeds of goldfish for that very reason.

For example:

Black moors do best with other fancy goldfish like fantails, Orandas, Ryukins or Bubble eyes because stronger, athletic slim-bodied fish like Common or Comets can out-compete them for food.

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When in Doubt, Always Remember that Less Stress is Best!

Diversity in the tank is interesting and important, no doubt.

But so is the happiness of your goldfish – and your sanity.


Get this:

Many times it’s just a bad idea to add more fish into the tank PERIOD because there just isn’t enough room to support the tank’s inhabitants.

This leads to all kinds of problems…

… Which can include having your fish feeling very stressed from overcrowding.

I think we all want the best for our pets.

But don’t lose hope!

You can always keep a separate community tank if you absolutely must have a variety of other types of fish. That way you won’t have to deal with any of the problems that come with mixing goldfish with other kinds of fish.

Here’s a tip:

Just be sure you don’t go too crazy, as too many tanks can make you stressed out if you are too busy to maintain them all. 😉

If You Just Have to Have An Algae Clean-up Crew, Here’s an Option…

So algae eaters aren’t a good fit for goldfish.

There’s good news:

Mystery snails are a good choice for goldfish, as they are relatively hardy and quite peaceful.

Be sure you quarantine any snails you get before adding them to your tank, as you don’t want them to bring in diseases from the pet store.

Some Final Thoughts

There have been and always will be people who claim to have success mixing different types of goldfish tank mates.

Granted, there are times when it does seem to work out every so often.


These are the exception, NOT the rule – in my humble opinion.

Things may seem to go “swimmingly” for a while…

But sooner or later, 99% of the time you will run into trouble.

One thing is for sure:

When it comes to goldfish keeping it is always better to be safe than sorry!

The risk of injury or even death to any of your tank’s inhabitants just isn’t worth it.

You don’t want to make any fatal mistakes with your beloved pet, which is why we wrote the complete guide to goldfish care, The Truth About Goldfish.

It has all the answers you will need for keeping a thriving, harmonious, disease-free goldfish aquarium.

You can check it out here:

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It’s Your Turn to Contribute

Now I want to hear from you.

Have you ever tried putting some more unusual specimens of aquarium life in with your goldfish?

What was your experience?

Leave your comment in the section below!

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  1. Maria February 5, 2017 at 4:51 am - Reply

    Can a comet fish and black telescope fish be in the same tank? I had the comet fish first and he seemed kinda lonely and I looked up online that said they are axial animales so i went to the pet store and got another fish which is the cute buggy eyed telescope fish I didn’t think much on which one made the best friend anyways I put them in the same tank pretty large tank. Anyways the comet fishes at first chased the telescope fish and bumped in to it so I thought maybe one day see how it goes do the comet fish kinds stoped chasing the telescope fish he did it maybe like 3 x that I saw but so the day passed by and then the comet fish started jumping it did it twice it scared me so I watch him and decide to take the telescope fish out and put it in another tank on its own. So my question is did I do the right thing or am I jus paranoid and it’s okay for them to be together. And is it fine to have just one gold fish on its own does he need friends ? If not does the telescope fish need a friend? I’m just a little confused / heartbroken

    • Pure Goldfish
      Pure Goldfish February 17, 2017 at 4:42 am - Reply

      Telescopes and comets don’t mix. Comets are way too active and moors can’t see well. They probably each need separate living quarters and separate friends 🙂

  2. Helen August 11, 2017 at 6:29 am - Reply

    New to goldfish. Have 5 shabumkins (the 6th got hole in the head yesterday 🙁 . In an outdoor pond, how do I clear up the poop? Wondering if that is why I lost Fishy 6. Having read your info, going to change the food from flakes (been given some bad adviice clearly!) Just worrying about the pop piling up in the pond (which is huge tractor tyre, lined with a good quality filer).

    Rating: 4.5
    • Pure Goldfish
      Pure Goldfish August 12, 2017 at 10:09 pm - Reply

      You will probably want to use a siphon/pump to give it a good water change.

  3. Helen August 18, 2017 at 7:01 am - Reply

    A couple of weeks in with intense study into keeping fish (who knew it was so complex!) and I’m thrilled to say the pond has been ‘hoovered’, water changed, plants added, rocks added, levels checked twice daily and we now have a perfectly balanced pond, fish are lovely and lively again, I have relaxed and situation all round is A1! 😊

    Rating: 4.5
    • Pure Goldfish
      Pure Goldfish August 19, 2017 at 9:25 pm - Reply

      Great to hear, Helen! 😀

  4. AyaLittleComet September 17, 2017 at 6:17 am - Reply

    I had a Comet and a Fantail goldfish in a tank once, and surprisingly it went well. Both got its own share of food, as the Comet, despite being fast, only takes one or two in its mouth at once and swim in circles near the base of the tank as it chews, leaving the Fantail to come to surface and gobble at least five at once and swim around lazily. I had no idea about the risks of having two different goldfish types back then. 🙂

    Rating: 3.5
    • Pure Goldfish
      Pure Goldfish September 24, 2017 at 11:29 pm - Reply

      Glad yours got along well, AyaLittleComet! Fantails can be one of the exceptions to fancy fish that do well with slim-bodied fish, but it definitely depends on the fish.

  5. Dallas December 1, 2017 at 2:19 am - Reply

    I have some uhh… different types of fish. I got 3 common goldfish plus I set a minnow net and got 4 small minnows, 5 pollywogs, and 2 small water bugs. So far, they’re doing okay. I’ve had em 4 about a week and they seem fine.

    Rating: 4
    • Pure Goldfish
      Pure Goldfish December 31, 2017 at 10:15 pm - Reply

      The minnows may eventually be eaten. Hopefully the water bugs will do alright 😉

  6. Cleo April 13, 2018 at 6:22 am - Reply

    So, my goldfish(an inch) keeps picking on my mystery snail. How can I prevent this?

    Rating: 4
    • Pure Goldfish
      Pure Goldfish April 15, 2018 at 10:20 pm - Reply

      Maybe try providing more hiding places for the snail, such as plants, cave hides etc. Your fish might also be bored. Make sure it has some fresh veggies to eat at all times.

  7. Jennie September 9, 2018 at 8:42 pm - Reply

    I have a koi pond – 5 koi and 1 fantail goldfish. I got all but 1 koi at the same time and everybody gets along, I just make sure the goldfish gets some food as he’s so slow. I live in the NE and, while the koi stay out and “hibernate” during the winter, I try to bring the goldfish inside because he had some swim bladder issues in a previous winter and I’ve read that cold weather can cause that to happen (although I didn’t move him in time last year so he stayed outside and survived a brutal winter – maybe he’d be fine staying out with the koi but I worry!) I have a nice 30 gal aquarium for him and was thinking of getting him a friend or 2 but after reading your helpful goldfish tips here I guess I’ll either let him be a solitary fishy or get a companion fantail. Also considering making him a year-round inside resident, otherwise I have an empty aquarium every year from May to October. Anyway, thanks for saving me from buying incompatible fish to keep my goldfish company!

    Rating: 5
    • Pure Goldfish
      Pure Goldfish September 17, 2018 at 3:28 pm - Reply

      You’re welcome Jennie!

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