Phytoplankton for dogs: Benefits, Dosage, and Side Effects

Medically reviewed by Nicole Wanner, DVM

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The profound impact Phytoplankton has on our planet is staggering. Phytoplankton for dogs is a sustainable source of nutrition that contributes to healthy brain activity, joint health, and so much more.

Not only does this hardy organism improve our lives it provides potentially endless benefits for our dogs. A microscopic marine organism that removes CO2 from our atmosphere feeds numerous sea creatures, converts cellular energy, and plays an essential role throughout our ecosystem.

71% of the Earth’s surface is covered in water, and the Phytoplankton produces 50% of the atmosphere’s breathable oxygen. Phytoplankton is a powerhouse in our ecological system as well as our bodies. This blog discusses Phytoplankton for dogs, including benefits, dosage, side effects, a comparison between krill, fish oil, plankton, and spirulina, as well as a buying guide.


Phytoplankton, also known as microalgae, are the foundation of the ocean’s food chain, feeding everything from microscopic zooplankton, krill, small fish, and multi-ton whales. Phytoplankton has similarities to landlocked plants in that both contain chlorophyll and require sunlight to live and grow.

Many Phytoplankton floats in the upper part of the ocean, where sunlight penetrates the water and waste from sea life provides the necessary nutrients. Those nutrients are nitrates, phosphates, and sulfur converting into proteins, fats, and carbohydrates. These nutrients are brought to the Phytoplankton from whales, as they cannot poop under pressure and must swim back up to handle their business. Phytoplankton then has enormous amounts of whale waste to extract the necessary nutrients for ecological processes. 

Krill vs. Fish Oil vs. Plankton vs. Spirulina


Bioavailability (The ability of a drug or other substance to be absorbed and used by the body)

Long Chain Omega 3 Fatty Acids

Dog Safe

Produce O2












Fish Oil









The table above offers a glimpse into the differences between Krill, Fish Oil, Plankton, and Spirulina.

As mentioned before, fish oil is widely known to obtain enough levels of Omega-3. Many people do not know that fish cannot produce EPA or  DHA : they get their Omega-3 by feeding on krill, and krill feed on algae to get their Omega-3. In other words, Marine Phytoplankton is the primary producer of essential fatty acids. Plankton is, therefore, a better and sustainable supplement to Krill, Fish Oil, or Spirulina.  


The consensus is that Phytoplankton may be good for dogs helping in improving skin, joint, and overall health. However, here is some supporting evidence to back up that consensus. There are six major classes of nutrients for dogs: water, protein, fat, carbohydrates, vitamins, and minerals. Phytoplankton is high in Omega long chains, Omega 3 fatty acids, EPA, DHA, nucleic acids, phenylalanine, proline, and magnesium, all of which are important for a dog’s health.

  • Omega Long Chains (EPA) & (DHA):  The omega-3 (n-3) long-chain polyunsaturated fatty acids are well accepted as being essential components of a healthy, balanced diet, having beneficial effects on development and in mitigating a range of pathological conditions. This long-chain polyunsaturated fat (otherwise known as the “good kind of fat”) supports your dog’s attention, memory, and trainability. Additionally, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) play an important role in heart health.

  • Nucleic Acids:  Nucleic acids are the most important macromolecules for the continuity of life. These macromolecules carry the genetic blueprint for life in all animals. Reinforcing nucleic acid intake through phytoplankton consumption may assist pets during times of disease or stress.

  • Phenylalanine:  This amino acid is essential to the normal growth of muscle tissue and hormone regulation, and it is converted into tyrosine in your dog’s body.

  • Proline:  Dogs use proline to make proteins, such as collagen. Collagen is found in the skin, bones, and joints. Proline is also involved in the general function of cells.

  • Magnesium:  Magnesium supports heart, joint and neurological health.


The range of Phytoplankton dosage for dogs changes with the health and size of your dog. Phytoplankton has high bioavailability, and some suggestions say only 1/16 teaspoon a day for any sized dog while others claim Small Dog = 1 Gram (1/2 teaspoon) per day, Medium Dog = 2 Grams per day, and Large Dog = 3 Grams per day. This measurement is based on a product containing zero fillers. There is no official dose, but here is a general guideline. Always consult your vet before giving any new supplements to your pet.

Dog Size

Marine Phytoplankton per day in grams

1lb – 10lbs


10lbs – 25lbs


25lbs – 50lbs


50lbs – 100lbs


100lbs +


*Dosage will be hugely dependent on breed, age, weight, level of health, metabolic type, and so forth, so consult with your veterinarian before giving your dog phytoplankton.


Side effects of Phytoplankton for dogs are mostly based on the ingredients and dosage of the product. Marine Phytoplankton powder or supplements are not controlled by the U.S. Food and Drug Administration, and there is a threat of contamination or toxic substances mixed in the powder. Be sure to check the lab results when purchasing Phytoplankton to ensure your dog is getting the healthiest ingredients.

 A large dosage of Phytoplankton can lead to side effects such as fatigue, heartburn, nausea, urination, prolonged bleeding times. Understand that these side effects are rare occasions as Phytoplankton is one of the most valuable sources of nutrition.

Omega Fatty Acid Side Effects:

  • burping

  • heartburn

  • stomach pain or discomfort

  • joint- pain

  • vomiting

  • constipation

  • diarrhea

  • nausea


Phytoplankton versus Fish Oil for dogs is a question pondered by many holistic dog owners. Phytoplankton is sustainable, whereas fish oil is not, also Phytoplankton contains zero mercury and heavy metals.

Both Phytoplankton and fish oil contain DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). Phytoplankton offers benefits that are different from fish oil. The tiny cell size and dense micronutrients seem to process in the system at a higher level, even in compromised digestive tracts.

Fish oil is generally less expensive and has higher levels of EPA. Naturally, if your dog takes fish oil for joint issues, it is best to stay on that track. Phytoplankton versus Fish Oil comes down to affordability and willingness on behalf of the dog owner.


When purchasing Phytoplankton, it is important to remember a few key objectives.  

  1. Sustainability-Phytoplankton is a naturally sustainable product and should be treated that way. Research your potential purchase and confirm zero harm is being done to the environment in the production process.

  2. Zero Radiation, heavy metals, or other toxic substances

  3. Non-GMO (genetically modified organisms)




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Ever since she was a puppy, she’d spend her days running and playing. I’d take her on walks, to the beach, and dog parks.

Unfortunately, at age 10, she started to limp after trips to the beach. It broke my heart to see her in pain doing what she loved the most. I started feeding her a raw food diet and added high-quality supplements to ensure her nutritional needs were met. Unfortunately, while she loved the food, the limping persisted.

I went to the vet, who looked over Biscuit and said she was likely limping due to joint inflammation. She gave us something to help. This worked well at first. Biscuit was moving around more freely, and was limping less. 

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