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How Do You Know When A Fish Is Hungry? 6 Simple Behavioral Signs

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By Lindsey Stanton

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Just like all other animals out there, fish need food to survive. They need nourishment, they need vitamins and minerals, and they need those calories. Since the fish in your home aquarium are confined to space and only have access to what you give them, feeding your fish the right amount is up to you.

So, how do you know when a fish is hungry? 

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How To Tell If Your Fish Is Hungry

Image credit: hedgehog94, Shutterstock

Here are some common signs;

  • Your fish is digging around the substrate (searching for food).
  • Waiting and the top of the aquarium (for feeding time).
  • Behavior changes (aggression).
  • Noticeable weight/size changes.
  • Slow or sluggish behavior.

Do Fish Know When To Stop Eating?

The funny thing about fish is that they will usually always eat, even when they are full. That being said, once they are full, they will probably stop eating on their own.

Sure, that is a great way of telling that they are full, but how do you tell if they are hungry? There are some really easy ways which you can tell that your fish is hungry.

The 6 Simple Behavioral Signs That A Fish Is Hungry

1. Stick To a Schedule

If you feed your fish once per day regularly, or even 2 or 3 times per day, if you miss the regular schedule, you can be sure that they are hungry. No, in the wild fish do not usually eat every single day. They eat when they catch food. However, at home, your fish get used to a certain feeding schedule, so missing it will mean the fish are hungry. You can also get an automatic fish feeder which we have covered in more detail here.

2. Observe their behavior

If your fish are swimming in areas they don’t usually visit, they may be looking for food. If your fish are digging around in the substrate, clearly searching for something, chances are that they are hungry. Fish that go to scavenge, but don’t usually scavenge, or go inspect the top of the aquarium, something they wouldn’t usually do, are both indications of hunger.

3. Fish size

If your fish is smaller, particular in weight and overall dimensions than that specific type of fish should be, it could be a sign of underfeeding. However, it could also mean that your fish is just small for its type.

4. Aggressiveness

If your fish is extremely aggressive and very quick to gobble down food once you feed it, you can be sure that it is very hungry. Yes, fish do feed quickly, but if you notice that your fish is or making an extra effort to eat as much as possible in record time, chances are that it has been hungry for a while.

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Image Credit: Yedidia Klein, Pixabay

5. Speed

If the fish is sluggish or slow, it might be a sign that you have not been feeding it enough for quite a while.

6. Cannibalism

Some fish might harass or attack other fish if they are hungry, but this is hard to judge as there can be many reasons for aggression.

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There you have it, the biggest telltale signs that your fish is hungry. If you notice more than one of these signs, your fish is probably dying for some food, so make sure to feed it more! Nobody wants a starving goldfish!

Featured Image Credit: Rethinktwice, Pixabay

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