Daphnia for Betta Fish: Everything You Need To Know

We as “keepers of fish” may take for granted that these living creatures have natural instincts that may be neglected in an aquarium setting. Betta fish, in the wild, do not have someone conveniently dropping food into their pond or rice paddies. 

They, instead, have to hunt for it.

Daphnia is the perfect food source to introduce into your Betta tank to spark those natural hunting instincts and give him a health/protein boost at the same time. 

Let’s explore Daphnia for Betta fish, so you can make an informed decision when it comes to this method of feeding.


What is Daphnia?  

Daphnia is considered a crustacean. It belongs to the planktonic genus and, depending on the individual species, ranges from 1 to 5 millimeters in length. They can be found in both fresh and saltwater areas.

These little critters have a segmented body and movements that resemble a flea, hence their nickname ‘sea flea.’

Because these crustaceans are preyed upon, some species have developed spikes or thorny protrusions that make them unpleasant to eat and difficult to digest for the predator. Of course, these will not be the ones available for purchase as a food source.

Most pet retailers and aquatic stores carry live, frozen, and freeze-dried Daphnia.

Aquarists over the years have also used Daphnia as an indicator of poor water conditions, as their small size makes them sensitive to toxins and pollutants. However, once your Betta has been introduced to Daphnia as a food source, these aquatic animals most likely won’t be around long enough to “gauge the water conditions.” 

If your Betta habitat is large enough with plenty of hiding places for these small crustaceans, some may escape being eaten. But don’t worry, their lifespan is only a few weeks, so there’s no worry about being “overrun” with this type of plankton. 

Why Do Bettas Need Daphnia? 

Feeding live Daphnia to Betta fish will spark their natural hunting instincts and relieve boredom in the habitat. There are also physical health benefits to feeding this live food. 

Daphnia is a great source of protein for your carnivorous fish and is a “pure” protein, not one that has been processed or bulked up with filler ingredients. This will help increase your betta’s energy levels, bring out his natural colours, and give his immune system a boost. 

Daphnia can also help relieve constipation in Betta fish (which can be a common health issue for this species). 

How to Feed Daphnia to Betta Fish 

Daphnia comes in three forms; live, frozen, and freeze-dried. Let’s discuss the pros and cons of each.

Live Daphnia  

This is Daphnia is their purest form – live and swimming – released into your tank and readily available for your Betta to hunt and eat.


  • Pure nutrition – no fillers
  • Great for stimulating your Betta’s natural hunting instincts
  • Easy to breed
  • Readily available


  • May have parasites (use a reliable source to keep these odds low)
  • May contain chemicals 
  • Risk of overfeeding (only put 4 to 6 daphnia into the tank at one time to reduce this risk).
  • Will need a separate holding tank or only buy small quantities at a time. 

Pro Tip: Do not scoop Daphnia out of ponds or other outdoor water sources. These could be carrying diseases, toxins from the environment, or parasites that can cause harm to your Betta fish.


This form of Daphnia comes in small cubes that have been frozen for your convenience. To prepare the Daphnia for your Betta fish, cut the cubes into small portions, then wait 15 minutes for it to thaw. 


  • Easy to feed
  • Closer to live than freeze-dried
  • Convenient
  • Keep for a long time
  • No chemicals or parasites present


  • Risk of overfeeding
  • Must thaw completely before feeding


This form of Daphnia has been dried and placed into jars for your convenience. They offer mostly the same benefits of live and frozen, but without the fuss and mess of cutting frozen cubes. They can also be used as a vehicle to deliver medications – just add it to the freeze-dried Daphnia and feed as you would any other food. 

Pro Tip: Soak 1.8 grams of Daphnia in water to rehydrate for 15 minutes before feeding. This cuts down on the chances of your fish getting Bloat. 


  • Convenient
  • Easy to find
  • No parasites or chemicals
  • Can use to hide medicine in


  • Must rehydrate before feeding
  • Chance of overfeeding

How Much Daphnia is Enough? 

You never want to overfeed your Betta as this can lead to health issues (Bloat, constipation, etc.). When it comes to Daphnia, we recommend only 1.8 grams once a day (or 0.9 grams twice a day). Live Daphnia should only be 4 to 6 (depending on the size of your Betta) and freeze-dried rule-of-fin is only what he can consume in one minute. 

You also do not want to use Daphnia as a regular diet. We recommend feeding this as an occasional treat (about once a week) or to relieve constipation (about 2 or 3 days).

Can I Feed Daphnia to Betta Fry? 

Betta fry will benefit from Daphnia, but not in the early stages of their development. Small fry cannot digest these crustaceans, so wait until they have reached about 3 to 4 weeks old – at this stage they have a developed digestive system that can break this food down into fecal matter. 

Daphnia is an excellent source of protein that will aid in your Betta fry’s development and overall health. 

Growing Your Own Daphnia  

Cultivating your own Daphnia is not difficult, but there are some things you will need to do.

Like any aquatic critter, you will need an appropriate habitat. We recommend using a 20-gallon tank; however, some aquarists use large totes or garbage cans. 

Keep the temperature between 72 and 85 degrees Fahrenheit. Daphnia can survive at higher temps, but it does lower their production.

Be sure to age the water before adding Daphnia. These crustaceans cannot tolerate chlorine and will die off quickly with normal tap water. 

Replace 20% of the water at least every 2 weeks – use your old aquarium water from weekly water changes for your Daphnia tank. You will also want a pH level between 6.2 and 8.9.

If you are growing Daphnia outside in a large container with plenty of surface area, you do not need to aerate the habitat. However, if you are growing Daphnia indoors, add enough aeration to just break the surface. Too much will kill off your culture. 

Daphnia needs at least 6 to 8 hours of daylight (sunshine is best). If you are growing indoors, use a sunlight lamp for 10 hours or place your Daphnia in a sunny window. 

Pro Tip: Watch the temperature of the water when keeping Daphnia in direct sunlight. 

In the wild, Daphnia east algae; however, you can also feed them yeast. Mix the yeast powder in water and feed only enough so that it turns the water in the Daphnia tank slightly cloudy. Feed again when the tank is clear. 

Experts in Daphnia cultivating recommend keeping two separate tanks going in case one crashes. It is also important to harvest the Daphnia regularly, as overcrowding will also crash the culture. 

Conclusion of Daphnia for Betta Fish 

Daphnia is an excellent source of protein for your Betta fish (and fry). Whether you feed live, frozen, or freeze-dried the benefits of this crustacean are numerous.

Daphnia should be fed as an occasional treat or when your Betta is constipated. However, be sure not to overfeed as this can also have adverse effects on your fish.

If you want to cultivate your own live Daphnia, this is a relatively easy process even for beginners. If you are happy sticking to the store-bought variety, be sure to purchase the Daphnia from a reputable source, so you can avoid adding parasites or chemicals to your Betta and his habitat.