The Future of Fish Feed: Insects, Algae, and the End of Fishmeal

If you want to understand the future of aquaculture, do not start with the fish. Start with what the fish eat.

Feed typically represents 50-70% of total production costs in commercial aquaculture. For salmon farming, it can reach 60%. For shrimp, up to 70%. This single line item determines profitability more than any other factor. And the traditional foundation of aquaculture feed -- fishmeal and fish oil derived from wild-caught forage fish -- is running into hard biological and economic limits.

The global fishmeal market consumes approximately 15-20 million tonnes of wild fish annually to produce about 5 million tonnes of fishmeal. That means we are catching wild fish to feed farmed fish, which, when you think about it, somewhat undermines the argument that aquaculture relieves pressure on wild fisheries. This is the paradox at the heart of the industry, and solving it is one of the most important challenges in food science today.

I have been following the alternative feed ingredient space closely for over a decade, and I can tell you: the solutions are no longer theoretical. They are commercial, they are scaling, and they are going to fundamentally change aquaculture within the next ten years.

The Fishmeal Problem

To understand why alternatives matter, you need to understand the problem with the status quo.

Fishmeal has been the gold standard of aquaculture feed for good reason. It has an excellent amino acid profile that closely matches what fish need for growth. It is highly digestible. It contains omega-3 fatty acids that transfer to the final product. And for decades, it was cheap and abundant.

All three of those advantages are eroding:

• Supply is constrained. Wild forage fish stocks are fully exploited or overexploited. The major fishmeal-producing fisheries -- Peruvian anchoveta, Nordic sandeel and sprat -- are subject to strict quotas that limit production. El Nino events can cut Peruvian production by 50% in a single year.
• Prices are volatile and trending upward. Fishmeal prices have roughly doubled over the past 15 years, from approximately $800/tonne in 2010 to $1,500-2,000/tonne in 2024. Fish oil prices have increased even more dramatically.
• Demand is growing. Global aquaculture production is projected to reach 140 million tonnes by 2030. Even with ongoing reduction in fishmeal inclusion rates, absolute demand continues to grow.

Insect Protein: The Black Soldier Fly Revolution

If I had to bet on a single alternative protein source that will have the most transformative impact on aquaculture feed in the next decade, my money would be on Hermetia illucens -- the black soldier fly (BSF).

Here is why BSF larvae are remarkable as a feed ingredient:

• Nutritional profile: BSF larvae contain 40-45% crude protein and 25-35% lipids on a dry weight basis. The amino acid profile is well-suited for fish nutrition, with particularly strong levels of lysine and methionine.
• Growth efficiency: BSF larvae can convert organic waste into biomass with a feed conversion ratio of approximately 2:1. They reach harvest weight in just 12-14 days.
• Waste valorization: This is the circular economy angle that excites me most. BSF larvae can be grown on food processing waste, brewery spent grain, fruit and vegetable waste, and even manure. They convert low-value waste streams into high-value protein.
• Scalability: BSF farming is highly automatable and can be done vertically, requiring minimal land.

Companies like Protix (Netherlands), InnovaFeed (France), Enterra Feed (Canada), and AgriProtein (South Africa) have built industrial-scale BSF production facilities. InnovaFeed's facility in Nesle, France, produces 15,000 tonnes of insect protein annually and is expanding. Protix recently opened one of Europe's largest insect protein facilities.

Feeding trials with BSF meal in salmon, trout, sea bass, and shrimp have shown that fishmeal can be replaced at inclusion levels of 25-50% without affecting growth performance, feed conversion, or fillet quality. Some studies report additional benefits -- improved gut health due to the chitin content acting as a prebiotic, and antimicrobial properties from the lauric acid in BSF lipids.

The main barrier remains cost. BSF meal currently costs $2,000-3,000 per tonne, compared to $1,500-2,000 for fishmeal. But the cost trajectory is downward as production scales, and the environmental premium is driving adoption even at a price premium.

Algae-Based Feeds: Going Straight to the Source

Here is an elegant logic: fish get their omega-3 fatty acids from algae, via the marine food chain. So why not cut out the middleman and feed fish directly with algae?

Microalgae like Schizochytrium, Nannochloropsis, and Chlorella can be cultivated to produce high concentrations of EPA, DHA, and protein. Schizochytrium, in particular, can accumulate DHA at levels exceeding 50% of its total lipid content -- making it an outstanding replacement for fish oil.

Veramaris, a joint venture between DSM and Evonik, operates the world's largest algal omega-3 production facility in Blair, Nebraska. Their facility produces EPA and DHA from natural marine algae through fermentation, and the product is already being used in commercial salmon feed by major producers. A single facility can replace the omega-3 equivalent of approximately 1.2 million tonnes of wild-caught fish.

On the protein side, algae face more challenges. While microalgae can contain 40-60% protein, the cell wall structure can limit digestibility in fish, and production costs remain high for most species. However, advances in cell disruption technology and strain optimization are steadily improving both parameters.

Macroalgae (seaweed) offer a different proposition. Species like Ulva, Saccharina, and Asparagopsis can be cultivated at sea with zero freshwater, zero arable land, and zero fertilizer input. Protein content is lower (10-25%), but they provide valuable micronutrients, pigments, and bioactive compounds. Current research is exploring seaweed as a partial feed ingredient -- not a complete replacement, but a valuable supplementary component.

Single-Cell Proteins: The Microbial Revolution

Perhaps the most futuristic category is single-cell protein (SCP) -- protein produced by bacteria, yeast, or fungi grown through industrial fermentation.

Methylococcus capsulatus is a methanotrophic bacterium that converts natural gas into protein with a composition remarkably similar to fishmeal. The company Calysta (now part of Adisseo) has commercialized this as FeedKind, producing it at industrial scale. The protein contains 70% crude protein with an excellent essential amino acid profile.

Marine yeast is another promising avenue. Companies like Arbiom are developing wood-to-protein technology, where second-generation wood sugars are fermented by specially selected yeast strains to produce a high-protein biomass suitable for aquaculture feed. This is a particularly compelling circular economy story -- turning forestry waste into fish feed.

Hydrogen-oxidizing bacteria represent perhaps the most radical approach. Companies like NovoNutrients and Solar Foods are developing processes where bacteria use hydrogen (produced by electrolysis of water using renewable electricity) and CO2 to produce protein. The theoretical resource efficiency is extraordinary -- no agricultural land, no freshwater, just electricity and air.

Plant-Based Proteins: The Established Alternative

I should note that the most widely used fishmeal alternative today is not insects or algae -- it is soy protein concentrate. Plant-based proteins already make up a significant portion of modern aquaculture feed formulations. Norwegian salmon feed, for example, has gone from over 90% marine ingredients in the 1990s to approximately 30% marine and 70% plant-based today.

Plant proteins are cheap and abundant, but they come with limitations:

• Anti-nutritional factors: Soy contains trypsin inhibitors, phytic acid, and saponins that can impair digestion and cause intestinal inflammation in carnivorous fish species.
• Amino acid imbalances: Plant proteins are typically low in methionine, lysine, and taurine -- essential amino acids for fish. These must be supplemented.
• Environmental trade-offs: Soy production drives deforestation in South America. Replacing ocean-sourced protein with land-sourced protein that contributes to habitat destruction is not a clean sustainability win.
• Consumer perception: Increasingly, consumers want to know what their farmed fish ate. "Soy-fed salmon" does not resonate positively in premium markets.

Plant proteins will remain an important component of feed formulations, but they are not the ultimate solution. The future is a diversified ingredient portfolio -- some plant, some insect, some algal, some microbial -- tailored to each species and market.

The Circular Economy Vision

What excites me most about the alternative feed space is not any single ingredient -- it is the systemic shift toward circularity.

Picture this: a food processing plant generates organic waste. That waste feeds black soldier fly larvae in an adjacent facility. The larvae are processed into protein meal and oil for aquaculture feed. The frass (insect waste) becomes fertilizer for crop production. The crops produce food for humans, and the cycle continues. Meanwhile, the fish farm's wastewater nutrients grow algae, which produces both omega-3 oil for feed and biomass for additional protein.

This is not science fiction. Elements of this integrated system are already operating in Denmark, the Netherlands, and Singapore. The technology exists. What remains is scaling it up, optimizing the economics, and creating the regulatory frameworks to support it.

What This Means for the Industry

I believe we are at an inflection point. Within the next five to ten years:

• Insect protein will become a standard feed ingredient at 15-30% inclusion rates for most carnivorous fish species.
• Algal omega-3 will replace a majority of fish oil in premium salmon feed formulations.
• Single-cell proteins will reach cost parity with fishmeal and begin displacing it at significant volumes.
• Feed formulations will be customized using AI and precision nutrition, optimizing ingredient combinations for specific species, life stages, and market requirements.
• The fish-in fish-out ratio for major species will approach or reach zero, finally making aquaculture a net producer of marine protein rather than a net consumer.

The companies and countries that invest in this transition now will have a decisive competitive advantage. The days of depending on a finite supply of wild forage fish to fuel aquaculture growth are numbered. The future of fish feed is being built in fermentation tanks, insect farms, and algae bioreactors -- and it is being built today.

I consult with aquaculture companies on feed innovation and sustainability strategy. If your organization is exploring alternative feed ingredients, I would be glad to discuss the science and the practical implications. Reach out through the contact page.

Prof. Dr. Zayde Ayvaz

Professor of Fisheries Industry Engineering at COMU. Researching AI-driven seafood quality assessment and sustainable blue food systems.