Understanding Phytoplankton: all you need to know

Marine Phytoplankton: What It Is, Why It Matters, and How It Can Transform Your Health and Garden

Every breath you take has something to do with marine phytoplankton.

These microscopic organisms — invisible to the naked eye, yet visible from space when they bloom across the ocean surface — produce an estimated 50% of the Earth's oxygen. They are the foundation of the entire ocean food chain. And harvested from the pristine waters of Vancouver Island, they are the single ingredient behind everything MARPHYL makes.

This post covers everything you need to know about marine phytoplankton: what it is, how it works, why it's nutritionally extraordinary, and how you can use it to nourish your plants, your body, and your pets.

 

What Is Marine Phytoplankton?

Marine phytoplankton are microscopic, photosynthetic organisms that live in both saltwater and freshwater environments. Like plants on land, they convert sunlight and carbon dioxide into energy through photosynthesis — but they do it far more efficiently, and at a scale that shapes the entire planet's atmosphere.

The word "phytoplankton" comes from the Greek phyton (plant) and plankton (wanderer) — they drift with ocean currents, forming the invisible living layer at the surface of the world's waters.

There are thousands of species of marine phytoplankton, broadly grouped into categories including diatoms, dinoflagellates, and cyanobacteria. Each group has unique characteristics:

Diatoms are among the most abundant, recognizable by their intricate glass-like silica cell walls. They are a primary food source for zooplankton and small fish.

Dinoflagellates are remarkable for their bioluminescence — they produce the ghostly blue glow you sometimes see in ocean waves at night. Some species are responsible for "red tides," large blooms that can affect water quality.

Cyanobacteria, also known as blue-green algae, are among the oldest life forms on Earth and are essential nitrogen fixers, enriching aquatic environments with nutrients.

MARPHYL's wild-harvested phytoplankton contains up to 80 different species — a multi-species profile that no single-strain, lab-grown algae product can replicate. Learn more about MARPHYL's phytoplankton and the science behind it.

Why Marine Phytoplankton Is the Foundation of All Life

Marine phytoplankton sits at the base of the entire ocean food web. It is consumed by zooplankton, which are eaten by small fish, which feed larger fish, which sustain marine mammals, seabirds, and ultimately, humans. Remove phytoplankton, and the entire chain collapses.

Beyond feeding ocean life, phytoplankton plays a critical role in regulating the Earth's climate. Through photosynthesis, phytoplankton absorbs enormous quantities of CO₂ from the atmosphere. MARPHYL's unique harvesting process takes this a step further — each production batch captures atmospheric CO₂ while generating oxygen equivalent to an 8-hectare forest, and the water is returned to the ocean at the same phytoplankton concentration it arrived with. Net-zero environmental impact by design.

This isn't just an interesting fact. It's the reason MARPHYL operates the way it does — as a guest in the marine ecosystem, not an extractor from it.

The Nutritional Power of Marine Phytoplankton

What makes marine phytoplankton so extraordinary as a nutritional source is its completeness. A single cell of phytoplankton contains:

• Omega-3 fatty acids (EPA & DHA) — the same essential fats found in fish oil, but without the heavy metals and without the middleman. Phytoplankton is where fish get their Omega-3s in the first place.
• Complete amino acid profile — all essential amino acids in bioavailable form
• Chlorophyll — the molecule behind photosynthesis, with powerful antioxidant properties
• Trace minerals and vitamins — including iron, magnesium, calcium, boron, and vitamins B1, B2, B3, B6, B12, C, and E
• Antioxidants including Superoxide Dismutase (SOD), one of the most potent antioxidant enzymes known

The key word is bioavailability. Because phytoplankton cells are microscopic — typically measuring just 2 to 200 micrometers — their nutrients are absorbed at the cellular level without the extensive digestion required to break down larger food sources. According to marine biologist Mark R. Edwards, microalgae store higher levels of nutrients than land plants, and are up to 300% richer in nutrients than terrestrial plants due to their ability to absorb nutrients through their entire surface rather than through roots limited by depleted soil.

This is not a supplement that needs to be broken down and processed. It goes straight to work.

 

Marine Phytoplankton for Your Garden

The same nutritional completeness that makes marine phytoplankton remarkable for human and animal health makes it transformative for soil and plants.

MARPHYL Soil Enhancers are OMRI Organic Certified, non-GMO, runoff-safe, and pet-safe. They work for every growing environment — vegetable gardens, houseplants, lawns, orchids, fruit trees, greenhouses, and hydroponic systems.

The lineup includes four formulations, each built on the same wild-harvested phytoplankton base. Not sure which one is right for your plants? Read our full guide to choosing the right MARPHYL Soil Enhancer.

MARPHYL All-Purpose is the foundation — a balanced, complete nutritional profile suitable for all plants at all stages. Use it throughout the growing season at a 1:20 dilution (1 part MARPHYL to 20 parts water), every two weeks.

MARPHYL +CalMag adds elevated calcium and magnesium — essential for plants showing signs of deficiency such as yellowing leaves, blossom end rot in tomatoes, or weak cell development. Dilute 1:20.

MARPHYL +Phosphate boosts phosphorus for root development, flowering, and fruiting. Ideal from mid-growth through harvest. Dilute 1:20.

MARPHYL +Minerals provides a concentrated trace mineral boost for intensively worked soils. Dilute 1:25.

Apply as a soil drench around the base of plants, as a foliar spray directly on leaves (early morning or late afternoon to avoid leaf burn), or directly in your hydroponic system. For full application instructions, visit the MARPHYL directions page.

Gardeners using MARPHYL consistently report stronger stems, deeper green foliage, increased fruit production, and greater resilience during heat and dry spells. The phytoplankton also feeds beneficial soil microorganisms over time, building a living soil ecosystem that sustains plant health beyond the growing season.

 

Marine Phytoplankton for Humans and Pets

The same wild-harvested phytoplankton that nourishes your garden is now available as a daily wellness supplement for humans, dogs, and cats.

MARPHYL Marine Phytoplankton Supplement is Health Canada approved (NPN: 80036064) and available in capsule and powder form. It provides EPA and DHA Omega-3 fatty acids directly from the source — skipping the fish entirely, and with it, the risk of heavy metal contamination found in fish oils. It supports mitochondrial energy production, cellular health, coat condition in pets, and overall vitality from a single whole-food ingredient.

For dogs and cats, marine phytoplankton is one of the most complete nutritional additions you can make to their diet. Its microscopic cellular size means nutrients are absorbed rapidly, and its natural profile of amino acids, antioxidants, and essential fatty acids supports joint health, skin condition, immune function, and energy levels. Read our guide to the benefits of phytoplankton for dogs.

If you came to MARPHYL through the soil enhancer, this is worth knowing: the product nourishing your garden can do the same for everyone in your household.

Explore the MARPHYL Supplement →

 

Where MARPHYL's Phytoplankton Comes From

Not all phytoplankton products are equal. Single-strain, tank-farmed algae — grown under artificial conditions with controlled nutrients — lacks the diversity and complexity of wild-harvested, multi-species phytoplankton.

MARPHYL harvests from the Strait of Georgia, where Pacific Ocean currents meet mountain snowmelt off Vancouver Island. This nutrient-rich, pristine environment allows phytoplankton to thrive naturally across dozens of species simultaneously. Seawater is pumped into adjacent reservoirs where phytoplankton reproduces under natural sunlight. A single milliliter arriving at the reservoir contains approximately 800 cells. At harvest, that same milliliter contains approximately 128,000,000 cells — a natural multiplication driven entirely by sunlight and clean ocean water.

The result is a product that is genuinely wild. Not approximated. Not synthesized. Harvested.

The Bottom Line

Marine phytoplankton is not a trend. It is the oldest, most fundamental food source on Earth — the organism that makes all other life possible. Harvested responsibly and applied intelligently, it has the power to nourish your soil, your plants, your body, and your pets from a single source.

That is the philosophy behind MARPHYL: one wild ingredient, benefits for all life.

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