Can Goldfish Eat Daphnia? (Experts Opinion!)

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Yes, Goldfish can eat daphnia. Both live and frozen daphnia will be readily accepted by your goldfish and are a great food source. Daphnia should be fed to your goldfish on a regular basis as part of a varied diet.

It is easy to see why goldfish have remained a firm favorite in the fish-keeping hobby. I currently have a 180 gallon (680 liters) aquarium filled with a mixture of Fantails, Ranchu, and Pearlscale goldfish. Out of all the tanks in my fish room, it is this one that everybody is stunned by.

Over the last few years, I have started to firmly believe that a variety of food is the key to healthy, colorful goldfish. When I give goldfish talks up and down the country and the subject of food comes around, there are a few questions I get asked every time. One of them is, Can goldfish eat daphnia?

What Are Daphnia?

Daphnia are small, planktonic crustaceans that measure around 0.01 to 0.20 inches (0.2-5mm) in length. Daphnia are often referred to as Water Fleas.

This common name comes from their jerky movement through the water which looks like fleas jumping through the air.

Daphnia spend almost their entire life swimming around looking for tiny morsels of food they can eat. They consume both microscopic waterborne creatures and organic matter.

Daphnia live in pretty much every aquatic environment, from swamps to freshwater lakes. They are able to multiply at an astonishing rate. Daphnia takes just one week to go from birth to adulthood.

Females can even reproduce without the aid of males. Daphnia are a live-bearing species, meaning the females give birth to live, free-swimming daphnia.

However, when conditions are less favorable to the survival of the colony, males are able to produce special eggs. These eggs are designed to allow the colony to continue even in the event of a major environmental issue such as a drought. The eggs can remain in a dormant state for long periods of time until more favorable conditions return.

Daphnia forms a major part of the aquatic food chain. In almost every waterway where they exist, fish will predate on them.

What Are The Benefits Of Feeding Goldfish Daphnia?

Daphnia is a rich source of Vitamins A and D. They also contain smaller quantities of Vitamins B and C as well as high levels of protein, fats, and carbohydrates (both sugars and scratches).

Vitamin A is essential for proper growth and development. Vitamin A also helps prevent infections from developing in fish. Much like us humans, fish require Vitamin D for proper bone development. Vitamin B helps stimulate appetite and supports tissue growth. Vitamin C is important for fish coloration and skin development.

Adding daphnia to your goldfish’s diet helps your goldfish get all the vitamins and minerals they need to be healthy. Having live food to chase also helps stimulate your goldfish’s desire to hunt, keeping them active and alert.

One further benefit of feeding a good quantity of daphnia to your goldfish is that it helps keep your goldfish’s digestive system moving. Goldfish can be prone to constipation. Daphnia helps prevent the issue, providing it is fed on a regular basis.

What Forms Are Daphnia Available In?

In the aquarium hobby, daphnia is usually available in two different forms, live and frozen. Both forms have their advantages and disadvantages. Below I have a look at their pros and cons.

Live Daphnia

Live daphnia are usually sold in a local fish store in either small bags or containers. Before you purchase your daphnia, hold the bag up to the light and check the daphnia is alive. Daphnia is constantly moving. If the daphnia in the bag is all just laying on the bottom, don’t buy them. There is no nutritional value in a bag of dead daphnia.

When you get the daphnia home, and you are ready to feed them to your goldfish, cut the corner off the bag and pour the contents through a net that is suspended above a bucket.

The daphnia will be caught in the net whilst the dirty water passes through into the bucket. The dirty water the daphnia were living in should not be poured into your aquarium.

Once added to the aquarium, the daphnia will dart around continuously. Your goldfish will instantly be attracted to the movement and will quickly devour as much of the daphnia as they can. Any daphnia not consumed straight away will survive in the aquarium for a few days until eaten by the goldfish.

The advantages of feeding daphnia to your goldfish include the fact that any daphnia which is not eaten straight away will happily swim around in the aquarium until eaten. Unlike dried food, you don’t need to worry about how much your goldfish will consume in a single feeding. Uneaten daphnia will not foul your tank water.

A major disadvantage of live daphnia is that they do not last very long. You need to buy them and feed them to your goldfish within a few days. As with all live food, there is always the chance of introducing disease into your aquarium when you feed live daphnia.

That said, the risk is very low, especially if you purchase your daphnia from a reliable local store. Never collect daphnia from wild sources as you will not know if the daphnia is disease-free.

Frozen Daphnia

Frozen daphnia is usually sold in individual cubes in a blister pack. When feeding frozen daphnia to your goldfish you can either drop a cube or two into your aquarium and allow your goldfish to pick at them as they defrost, or you can take a cup of aquarium water, defrost the cubes of daphnia in the cups, then, once the cubes have defrosted, pour the daphnia soup back into the aquarium.

The main advantage of feeding frozen daphnia to your goldfish is that you can keep a blister pack in the freezer for months, just popping a cube out whenever you need to feed one.

On the flip side, the disadvantage of frozen daphnia is that there is no way of knowing if the daphnia was alive and healthy before freezing. If the daphnia were dead before freezing, their nutritional value to your fish will be much lower. Bearing this in mind, only buy frozen daphnia from a reputable supplier.

How Often Should You Feed Daphnia To Your Goldfish?

Daphnia is a great source of vitamins and minerals for your goldfish. However, they are not suitable as a staple source of food. Daphnia should only be fed as part of a varied diet.

I feed my goldfish 3 to 4 times a day. I try to make sure at least one of those feedings is alive or frozen food, including daphnia. If you are feeding frozen daphnia, only add as much as your goldfish will consume within a few minutes.

If feeding live daphnia, feed as much as your goldfish will consume within a few days as the uneaten daphnia will live on in the aquarium.

What Other Live Or Frozen Foods Can Be Fed To Goldfish?

There are many other varieties of live or frozen foods your goldfish will eat. We have articles on each of the following:

In Conclusion

Daphnia makes a fantastic addition to a Goldfish’s diet. Packed with goodness, daphnia makes a great alternative to goldfish flakes or pellets. Feed as part of a balanced diet and your goldfish will grow strong and healthy.

About the Author

I’ve been keeping, breeding, and showing tropical fish for nearly 30 years. Over that time I’ve done it all! I’ve had great success and I’ve made some really foolish mistakes (like the time I bought an Asain Walking Catfish). Read more…
Richard James

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