Clean up algae and break down organic waste in the tank
Offer attractive colors and patterns to the aquarium
Get along well with goldfish – peaceful and many are too big to eat
Snails are a superior alternative to algae-eating fish like Plecos. Because they are peaceful goldfish tank mates, you don’t have to worry about them hurting your fish – but you still get the benefits of algae removal. They come in all colors, shapes and sizes for you to choose from. Some people even use smaller snails as a food source for their goldies. Larger snails are ideal if you are looking for something to help keep the aquarium cleaner without getting eaten. When it comes to identifying and destroying rotting plant material or being your mini algae scrubbing cleanup crew, these guys can’t be beat! (Warning: you might find you spend more time watching them than you do your actual fish!)
The only shrimp big enough not to get eaten by bigger goldfish!
Doesn’t require acidic water conditions like most other shrimp species
Keeps the aquarium cleaner by foraging for food scraps on the filter intake
Most goldfish would devour any shrimp in rather short order – but not the Bamboo Shrimp. This fellow is just too big to fit in their mouths! As adults, they are 4″ long. Another super cool thing about them is that once they settle in to your aquarium, they change color from simple brown to either bright red or blue (most commonly)! They can even change color based on their mood. As far as requirements go, they aren’t demanding, but don’t like to live alone – be sure to get at least one Bamboo Shrimp friend. Shrimps have a very low bioload on the tank and are fascinating to watch. The best part? They don’t need warm temperatures (though they do just fine in warm water too), and can tolerate a range of 68-85 degrees F. They love tanks with lots of plants and enjoy grazing on algae.
Beautiful little loach with very interesting patterns
Fairs best in water on the cooler side
Eats algae and uneaten food from the bottom of the tank
The Hillstream loach (or Butterfly loach), like goldfish, is native to Asian waters and is a peaceful fish with an intricate pattern. Unlike suckerfish, their mouths are not equipped to do any damage to a goldfish. This makes them an excellent alternative to plecos for a fancy goldfish tank. These fish grow to be 2.5-3″ large and enjoy areas of the tank that have faster-moving water. They love algae and will graze on any they can find, as well as sinking algae tabs. Some find blanched kale leaves make an excellent food source for them, and kale is not quickly consumed by the goldfish. Hillstream loaches prefer colder water ranging from 61-75 degrees F. They can grow up to 4″ in length, and are best kept as fancy goldfish tank mates. These fish can be challenging to find as they are very difficult to breed in captivity. Reticulated Hillstream loaches have a stronger color pattern and are even more rare. If eBay doesn’t have them, you can try Amazon here.
Provides a nice contrast to the colors and size of a goldfish
Many fish keepers have had success with keeping their slower-moving fancy goldfish with White Cloud minnows. The white clouds are usually fast enough that the goldfish don’t catch them. They’re also one of the few other fish species (like goldfish) that tolerate cooler water as well as warm water. And the best part? Their streamlined appearance make a nice contrast to larger, more deep-bodied goldfish. White Clouds come in several variations, including golden and silver. There are even long-finned white clouds if you want something extra special. They do best when kept in schooling groups of 5 or more.
A coldwater fish native to Asia, the Weather loach (also called Dojo loach) is an easy, typically peaceful pet with few demands. They have been occasionally known to nip at slower-moving fancy goldfish, so goldfish keepers find they do best with slim-bodied fish such as Commons, Comets and Shubunkins and make a good addition to a pond. Dojos can be found in a wide range of colors, from bright solid gold without spots and dark eyes (known as the Golden Dojo) or brassy, silver or brown variations with or without spots. The name “Weather loach” refers to its ability to sense changes in barometric pressure, causing it to behave erratically before a storm or weather front. They can become tame enough to eat from your hand! Dojos can grow to be quite large (10-12 inches long) so sufficient room is required, as well as a fine sand substrate for them to burrow in. They also prefer to be kept in groups of 3 or more to prevent the stress of being kept alone. These fish tolerate a wide range of temperatures, from 50-77 degrees F.
Reasons Only Some Fish are Compatible with Goldfish
It’s important to select only suitable goldfish tank mates to avoid the problems below.
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 and carry far less dissolved oxygen.
Goldfish (slim-bodied ones anyway) prefer temps in the 65-80 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.
Of course, in a home aquarium, many times seasonal fluctuations do not occur even for goldfish not kept with tropical fish.
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 some 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.
Many 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.
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.
Even the supposedly peaceful Bristlenose Pleco has been reported to attack goldfish!
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 – if it can catch it.
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!
Slim-bodied breeds will probably turn any fish smaller than themselves into shark-bait.
Most people don’t have problems with White Clouds getting eaten by their fancies, but occasionally it can happen if the goldfish figures it out – and one by one, they’ll all disappear.
The other fish have to be fast or large enough so this can’t happen.
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 and some other select species 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.
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.
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.
When in Doubt, Always Remember that Less Stress is Best!
Diversity in having different goldfish tank mates is interesting and important, no doubt.
But so is the happiness of your goldfish – and your sanity.
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 tropical or saltwater 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.
Whatever you do, always be sure you quarantine any new inhabitants before introducing them to your aquarium in order to avoid disease outbreak.
One method that works for many smaller species (such as keeping betta fish with goldfish) is to use a hang-on breeding box attachment for your tank.
An avid goldfish breeder and keeper for nearly 20 years, Meredith Clawson is the founder of the Pure Goldfish website and author of the book The Truth About Goldfish. Pure Goldfish has been featured in Wikihow, Wikipedia, The Aquarium Guide and more.