Do you know goldfish don’t have a true stomach? They digest food as it moves through their intestine and extract the nutrients in the meantime as the food passes through them. Also, they don’t have teeth like us. Instead, they have pharyngeal teeth. So, can goldfish eat cucumbers?
It’s easy and convenient to think that goldfish meet all their nutritional needs from flakes and pellets. But that’s a misconception, my dear friend. As a matter of fact, they’d highly benefit from consuming fresh produce.
Keep reading to know!
Can Goldfish Eat Cucumbers?
Yes, goldfish can safely eat cucumbers a couple of times a week. However, you’ll need to boil/blanch and skin it before feeding. Besides hydration, cucumbers impart a lot of other benefits to goldfish. For instance, its fibrous content helps ease constipation, vitamin K helps blood clot and keeps the bones healthy, and vitamin A aids with eyesight, reproduction, and immunity.
Here’s an excellent video of goldfish snacking on cucumbers. Don’t miss it!
As always, I scoured through different forums to look up authentic and unfiltered answers. And to my sweet surprise, I discovered that many hobbyists regularly include cucumber in their fish’s (including goldfish) diet.
Do you want to know what they have to say? Keep reading!
Can Goldfish Eat Cucumbers? Real Answers By Real People!
Note: All the opinions expressed belong to respective owners!
“Yes, mine actually love cucumbers. Not as much as my snail does, though!”
“I just slice, peel off, remove the seeds, and weigh them down to the bottom.”
“Whenever I put cucumber or lettuce in the tank for my snails, my moors will always pick away at them too. They’ll nibble here and there.”
“Yes, I think cucumber is perfectly fine for your fish. But I would take the skin off around the cucumber first, though. Isn’t that stuff sort of like the shell the peas are in?”
“Cucumber is good for fish. It is known to cure swim bladder infections.”
So, it’s a big YES from our fellow hobbyists. Cucumbers are good to go!
Before we discuss the health benefits of cucumbers in goldfish, let’s look at their nutritional content first, shall we?
Nutritional Content in One Medium-Sized, Unpeeled, Raw Cucumber:
- Total fat: 0
- Carbs: 6 grams
- Protein: 3 grams
- Calories: 30
- Fiber: 2 grams
- Vitamin C: 10% of the recommended daily value (DV)
- Vitamin K: 57% of the DV
- Manganese: 9: of the DV
- Potassium: 12% of the DV
- Magnesium: 9% of the DV
Goldfish need vitamins and minerals just like any other animal. An incomplete or improper diet can result in deficiencies and the subsequent onset of severe health conditions like stunted growth, weakened immune system, or even death.
Health Benefits Of Cucumber For Goldfish

Cucumbers are only praised for their hydrational properties, but these versatile veggies come loaded with several vitamins and nutrients beneficial for goldfish. It’s rich in vitamin C and K, as well as many minerals that work collectively to boost immunity and wellbeing.
Vitamin C Builds Immunity and Heals Wounds
As evident from the table above, cucumbers are rich in vitamin C. Vitamin C strengthens the fish’s immunity, helps wounds and injuries heal faster, and neutralizes the harmful effects of chlorine on fish.
Vitamin C’s antioxidant and anti-inflammatory properties play a crucial role in maintaining goldfish’s health.
Minerals Promote Healthy Cell And Metabolic Enzymes
Although cucumbers don’t contain two of the most crucial minerals that fish need – calcium and phosphorus – it’s rich in magnesium, potassium, and manganese. These minerals promote healthy cells, the immune system, and metabolic enzymes.
They’re even pivotal in maintaining bone, teeth, and scale health in goldfish.
Vitamin K Helps With Bone Mineralization
Vitamin K plays an indispensable role in blood coagulation and bone mineralization in fish. And luckily for us, cucumber is an excellent source of vitamin K.
Lack of this vitamin is linked with anemia, increased blood clotting time, histopathological changes in gills and liver, and mortality.
Fiber Boosts Metabolism And Digestion
Since goldfish don’t have true stomachs, they’re pretty prone to digestive complications. And cucumbers contain just the right amount of fiber to boost their metabolism and digestion.
While fiber is indispensable to facilitate digestion, it should only be given in moderate amounts. This way, it will work as a laxative and help the fish with indigestion and constipation.
How To Prepare Cucumbers For Goldfish?

First, wash your hands thoroughly before you start. Next, gently scrub and run it under cold water to remove any dirt present. You can use your fingers or a vegetable scrubbing brush for that.
The next step is important.
To prevent chlorine present in tap water that you just used to rinse cucumbers from getting into the veggies and subsequently tank, use a paper towel to pat dry them.
If you still aren’t convinced, we suggest cleaning the cucumber using distilled water instead of tap water.
Like all fish, goldfish have small mouths. Therefore, cucumbers need to be skinned and diced into small cubes. They shouldn’t be any bigger than 1mm (0.10 cm) to 2mm (0.20cm) in size.
Next, heat around 1 inch (2.5 cm) of water in a pot and let it come to a boil. Then place the steamer basket containing prepped cucumber cubes into the pot and cover for 1-2 minutes.
Once boiled, immediately transfer the cubes to a bowl of ice water to cool them and stop them from cooking.
Finally, scatter the prepared cucumbers into the tank. If there are only a couple of goldfish, adding just a few tiny pieces will suffice. For a tank full of goldfish, you’ll need to add a few generous spoonfuls.
A few hours after the fish are done eating, swiftly remove the leftovers. As they’re organic matter, they’ll rot and pollute the tank easily!
How To Store Cucumber For Goldfish?
If you’d like to prepare and store cucumbers for convenience in the future, it is possible. You need to transfer the prepped veggies into an airtight container and refrigerate them for around 3 days.
If the cucumbers start looking brown or soften over time, get rid of them and start with a fresh batch.
Frequently Asked Questions

What Fruits Can Goldfish Eat?
Goldfish can eat a wide variety of fruits provided that they are ripe and don’t have bruises or blemishes. Here’s a shortlist of fruits you can give them:
- Apples
- Mangoes
- Grapes
- Oranges
- Pears
- Raspberries
- Blueberries
- Strawberries
- Bananas
As healthy as fruits are, it’s recommended that you limit their food intake to just 2 times a week.
What Vegetables Can Goldfish Eat?
Goldfish can enjoy a wide range of vegetables. But make sure the veggies look firm and heavy without wilted spots or blemishes. Here’s a shortlist of veggies you can give them:
- Spinach
- Lettuce
- Sweet potatoes
- Potatoes
- Carrots
- Lima beans
- Peas
- Cauliflowers
- Cabbages
- Broccoli
- Zucchini
- Pumpkin
You can store prepped vegetables just the way you’d store blanched cucumbers – refrigerated in an airtight container for up to 3 days.
Can Goldfish Eat Carrots?
Yes, goldfish can eat carrots. Just like with cucumbers, you should first boil and blanch them. Carrots are a great source of fiber and vitamins, both of which are essential for goldfish.
For instance, carrots are rich in beta-carotene, which helps to improve the health and appearance of skin and scales.
Carrots are also rich in nutrients like potassium, vitamin A, and magnesium – all of which are good for your goldfish.
Can Goldfish Eat Tomatoes?
It’s not really recommended to feed goldfish tomatoes. That’s because tomatoes are known to cause intestinal blockage in goldfish. So although tomatoes are a great source of vitamin C and antioxidants, it’s best to fulfill these nutritional needs through other sources.
Can Goldfish Eat Bananas?
Bananas make an excellent choice of fruit for goldfish. Since bananas have a soft texture, your fish can easily digest the fruit while retaining all of its nutritional benefits.
In addition to enhancing digestion, bananas also boost a fish’s immunity due to their high antioxidant content.
Can Goldfish Eat Lettuce?
Lettuce is probably among the most widely fed veggies to goldfish and other fish everywhere. Not only does lettuce contain lots of different kinds of vitamins, but it is also super easy to digest.
When serving lettuce, make sure to chop it into small pieces so your goldfish can nibble on it comfortably.
Can Goldfish Eat Green Beans?
Yes, goldfish can safely eat green beans in blanched form. You can give them green beans to your fish 1-2 times a week. They contain a decent amount of calcium, one of the two minerals super necessary for fish.
Besides that, green beans also contain vitamin K and vitamin B in abundance – further encouraging your fish’s health.
Final Words: Can Goldfish Eat Cucumber?
Yes, goldfish can safely eat cucumbers. You can add this healthy veggie to their weekly diet regime without any problem!
Just make sure to boil, blanch, and cut the cubes into small pieces so they can fit inside your fish’s mouth. Also, remove the leftovers right away as organic food will decompose fast and pollute the tank.