Do Goldfish Eat Smaller Fish?

Do Goldfish Eat Smaller Fish?

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Having a goldfish as a pet can be very rewarding, and over time one may be tempted to get your water-borne pet some companionship. Some of our readers asked if it’s safe to drop much-smaller fish into the tank.

Yes, goldfish will eat other fish. A challenge for them is that they can only eat fish that are sized to fit in their mouth.

Some say it’s not wise to drop specimens into your tank that are smaller than your fish. But that’s not necessarily true, for the reason noted above.

Also, goldfish are not known for their predatory skills, so if you know smaller fish that are fast-moving, perhaps it might work out.

Additionally, goldfish have no front teeth to grab and hold prey. They must catch prey from behind, them suck and swallow them whole.

They are omnivorous, and not purely carnivorous. Much of what is in fish food is plant material, or insects or their larvae.

What Goldfish Eat

In actuality, goldfish will eat almost anything it can catch or nip at. Sometimes they can appear to be like picky shoppers, picking and pecking at tiny floating objects ~ sometimes spitting out stuff they dislike.

But like other animals, at times they get quite hungry. It’s during these periods when you should watch the tank closely if you also have other, much smaller, fish.

Solutions? Be sure to feed your goldfish consistently, not too much but over a schedule with hours of breaks to let the food particles settle, among other benefits.

Too much fish food can be unhealthily for your pet, and even be potentially fatal.

Aside from a solid feeding schedule, focus on providing a balanced diet to prevent the urge to eat other fish.

This might include other live fish, like tiny shrimp.

Goldfish can live for years and reach sizes that require a bigger tank! Feed them properly and discover a pet to keep you company over a good chunk of your lifetime.

Goldfish Can Get Territorial Over Time

Goldfish might eat other smaller fish, but they are not known for attacking other aquatic life.

Older or larger goldfish can become territorial, common mostly among species that must fight for their share of food. When this occurs goldfish could indeed attack other fish.

When old goldfish grow super big, don’t hesitate to get it into a larger tank. See Related Questions below for details regarding goldfish aggression.

List of Fish Smaller than a Goldfish

Many varieties of freshwater fish mature into the tiny size they are destined to be. The list of fish small enough to be consumed by goldfish is just about innumerable.

Here’s a list of some, all of them aquarium-worthy:

  • Several species in the Rasbora family
  • Orange guppy
  • Dwarf pea puffer
  • Indonesian superdwarf
  • Dwarf pencilfish
  • Rosy loach
  • Least killfish
  • Baby goldfish

On the last one, yes, adult goldfish could find themselves eating tiny goldfish ~ even goldfish eggs! They don’t even care if it’s their own eggs.

Baby goldfish fall prey to many other species of fish and only a small percentage of them grow to adulthood.

Due to this, goldfish eggs are hatched in batches numbering in the hundreds. You may one day wonder where the big cloud came from.

Tips for Maintaining the Small Goldfish Bowl

Ever stare at your goldfish and wonder what it’s like when your whole world is enclosed in a small space encircled by glass?

That the poor goldfish also tends to be a tad messy ~ makes pet-keeping that much more challenging.

Note: as goldfish grow, it may seem like the bowl is messier. This is especially true if you don’t upsize the bowl or aquarium. Bigger fish eat more amd therefore defecate more.

Words on Aquarium Care

First off, change the water often, but do NOT use tap water. All kinds of chemicals are added to the water we drink, bathe in, and use for other purposes.

The main danger is chlorine, a chemical deadly to small fish species.

When to Change Goldfish Bowl Water

It’s pretty simple: when the water gets rather milky, and doesn’t settle well over a period of time. Much of the tiny particles are either waste discharged from your goldfish, or degrading pieces of fish flakes.

Also, goldfish bowls are known to be ripe places for algae blooms. Not all algae is bad, however, since it breaks down particles and provides oxygen.

Fish bowls and aquariums do not require bright clear water all the time. And you can get help ~ living assistance. Freshwater leeches and snails can constantly suck the film off the glass.

Snails are known to eat organic debris, algae, food flakes, and even stuff that fall between the cracks and crevices between pebbles and small rocks at the bottom of the tank.

Tips for Cleaning a Goldfish Tank

First of all, of course, don’t use water straight from a faucet. Here are some more nuanced tips.

  • Don’t replace all the water at the same time. Doing so probably would prove fatal for the fish. Leave about 40% of the old water and fill the rest with clean (non-tap) replacement H2O.
  • During the process, slow down. Pouring new water slowly lets your pet acclimate to the new environment. Just add de-chlorinated water in small batches. Pour a little and see the fish’s reaction.
  • Just tossing a goldfish into a bowl of fresh water would very likely send the fish into shock. Water inside these bowls develops its own chemical levels ~ as well as remnant food particles.

Goldfish Eating Tendencies

Goldfish are not carnivors. They are considered opportunistic feeders. They float around with eyes and nose sensor active, hoping for that lucky find.

As stated above, they eat a great variety of plant matter, algae, insects, larvae, eggs, and even crustaceans.

In the wild, in inland fresh waters, goldfish range quite wide to find that food. They love sandy substrates, and aquatic plants; and will munch on insects like water fleas, and even ingest some zooplankton.

Which makes hosting a goldfish among the easiest pet-care experiences around. Still, improper maintenance and care, plus foolish decisions especially with water changes threaten the little creatures.

But the simplicity in feeding them almost anything ~ fish flakes, small insects or even small peas ~ keep it simple. Just try not to over feed!

Related Questions

Question: Do goldfish really have teeth?

Answer: Yes, but not the usual front-of-the-mouth type. Theirs are in the back of the throat, used for grinding and chewing ~ but not biting. They are too far back to see, let alone get used for grabbing prey.

Question: Just how aggressive could a big old goldfish get?

Answer: Very. Some owners have used words like vicious or mad to describe the aggressive behavior. See the paragraph above about being territorial. Big major predators can be territorial, put it that way.

Question: Just how big can mature goldfish grow?

Answer: Up to a foot long! Don’t forget to grow the tank along with it. Healthy, well-attended goldfish can live 15 years or so.

Question: Is there something to be done to use tap water in a fish tank?

Answer: Yes. Purchase a water conditioner. This neutralizes the chlorine to make it safer for fish.