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What Vegetables Can Fish Eat? [Tropical and Marine]

Sometimes you just run out of fish food or alternatively you just might want to provide as many different nutrients to your tropical fish as possible. Well, luckily some of the foods you probably have stored right in your own fridge are super nutritious and edible for your fish. In this article, we will explore as many options as possible.

So what vegetables can fish really eat? From my years of aquarium experience, here are the vegetables tropical and marine fish will eat – broccoli, cauliflower, zucchini, cucumber, lettuce, spinach, peas, squash, yellow beans, green beans and Brussel sprouts.  The leafy ends of carrots and other vegetables that are typically thrown away are also good options to feed the fish.  

There are probably other vegetables or fruits that some hobbyists have had luck with that I didn’t capture above however, that list should keep you going for a while. There are some precautions and preparations you should take with some of these foods and I will discuss these in more detail below.

What Fruits and Vegetables Can Tropical Fish Eat? (Precautions and Recommendations)

What you feed your tropical fish will be typically determined by the size of the fish and if they are herbivores, omnivores or carnivores. Herbivores are more likely to eat the vegetables you provide however, that’s not to say the carnivore won’t try them.

For fruits, I recommend grapes sliced in half with the peel taken off. Banana can also be used if it is not fully ripe. Just beware that fruits tend to break up easier in your water and if the fish don’t consume them, then the sugars will need to be somehow cleaned out of the tank.

Herbivores and omnivores will be better suited to digest fruits and vegetables however, carnivores will not turn away food when hungry.

  • For smaller sized fish, just remember they might not be able to bite into green beans but nibbling on spinach or partially boiled zucchini will be just fine.
  • Larger fish can pick at chunks of cucumber or partially boiled broccoli and cauliflower. They will also eat the other leafy type foods.

Just remember when selecting fruits or vegetables, consider the size of the fish and how easy or hard it will be for them to bite into the food and digest. Don’t be scared to boil the veggies briefly to soften them up.

Bonus precaution; take seeds out of the food such as cucumber seeds or any type of seeds. If by chance your fish is able to fit the whole seed in their mouth, they will most likely end up choking on it. 

Feeding carrots to fish

What Vegetables Can Marine Fish Eat?

Some popular types of veggies to feed saltwater fish include, broccoli, peas, squash and different types of lettuce. Make sure to blanch non-leafy veggies to ensure the food is easy enough for the fish to bite pieces off.

For any veggies like peas and cucumbers, take the peel off as this part of the vegetable might prove to be troublesome for the fish to chew through and consume. This part of the veggies can also be a choking hazard.

Other than those suggestions, just try different foods until you find the ones that your fish take a liking too.


When feeding lettuce or the leafy ends of carrots to your fish, use a large plastic clip such as this one from Amazon to hold the lettuce in place. This also makes it easier to take the leftovers out of the tank. 

What’s Better Frozen, Fresh or Canned Vegetables for Aquarium Fish?

You are not just limited to using fresh vegetables for your aquarium fish. Feel free to use canned or frozen as well. This makes it even easier to have these fish treats on hand.

I would recommend using fresh and frozen the same as in blanching most of the vegetables before feeding.

When using canned vegetables, you will be able to get away with using canned peas and just shelling them and feeding without blanching as the peas should be soft. Use your better judgement when preparing these foods for your fish, always thinking about the size of the fish and if they will be able to nibble on these foods without choking.

For further reading similar related to this topic, I have an excellent article on this site about what you can feed your aquarium fish if you run out of fish food. Make sure to check it out!

What Vegetables Can Betta Fish Eat?

I thought it would be worthwhile talking about Betta fish briefly because of how popular this fish is and the fact that Bettas are carnivores. If a Betta is carnivorous, you would think that the fish wouldn’t eat any vegetables however, I have seen them pick away at some foods other than blood worms.

First off, I would say that I would not recommend feeding Betta and types of fruits, just stick to the veggies. I have read that fruits will cause issues for the fish.

Recommended vegetables for a Betta fish would be any type of lettuce or spinach as well as blanched peas and broccoli. You could also put in a slice of cucumber or zucchini to see if the fish takes to those.

What Vegetables Do Koi Fish Eat?

Koi’s are not picky fish in my mind. I would say go ahead and try just about any vegetable you want with them. Make sure to blanch some veggies and chop others into small pieces.

When I think of Koi fish eating, I feel they eat first and taste later, so by the time they figure out they don’t like something it’s to-late for them to turn it away.

One rule of caution that I found online when researching Koi fish was they love to eat garlic. I haven’t seen this but can imagine that they would eat something like this. For whatever reason, Koi are attracted to the smell of garlic. So if you have some, give it a try. Source.

What Vegetables Will Neon Tetras Eat?

I put this section in here because I have a 10 gallon tank with a small school of Neon Tetras I have been wanting to feed some veggies to for some time now. I have yet to do so and I apologize. Once I do, I will update this article.

What I can tell you is what I will attempt to feed them. I am planning on feeding the Neon’s some lettuce, spinach and boiled peas with the outside of the pea removed. I might just try some cucumbers as well. Again, when I do I will update this article.


In conclusion, you can see that just trying different types of vegetables is the best route to take. I would recommend trying one type of veggie at a time and try it a few different times. Maybe pick one veggie of the month and just offer that to the fish while taking note, on whether they consume it or not. Then the next month try a new one.

You have to give the fish the opportunity to build up the courage to attempt to eat what you put in the tank while also considering that sometimes when you feed them they just might not be hungry. Or, they just aren’t hungry enough to take the chance of eating something new and strange in the aquarium.

One veggie I haven’t mentioned but thought of is carrots. I haven’t tried boiled carrots yet in any of my tanks but i think with their bright color they might just be a big hit with some fish.

Most importantly, just make sure you blanch/boil harder veggies and get any uneaten portions out of the tank as soon as you feel the fish have finished eating or just aren’t biting.

Good luck and happy feeding.

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