The problem with farmed seafood

Alternative Feeds for Aquaculture

• Black soldier fly larvae repeatedly cited as a promising fish feed: turn agricultural waste into protein and fertilizer, can be farmed at scale, and are already used commercially.
• Duckweed and algae suggested as fast-growing, high‑density protein sources that could replace fishmeal and provide omega‑3s, especially if production is automated.
• Some confusion and correction around “algae oil”: industrial omega‑3 oil often comes from Schizochytrium (a non‑photosynthetic microbe fed on sugars/waste), so its climate benefit is mainly replacing fish oil, not carbon capture.
• Concern that algae’s “100% consumable mass” is overstated and that nutrient content, taste, and digestibility also matter.

Carbon, Climate, and Food Systems

• Debate over whether algae‑based feeds materially help with CO₂: most ingested carbon is exhaled as CO₂; real gains come from not burning fossil carbon and from protecting natural sinks.
• Some argue marine systems (sinking biomass, shells) are important long-term carbon sinks that fishing can disrupt.
• Side discussion on livestock emissions, especially cattle and grass‑fed vs grain‑fed beef, and how land-use change and methane dominate their climate impact.
• Broader point: greenhouse gas metrics alone don’t capture all sustainability issues (e.g., habitat loss, runoff, pesticides).

Wild vs Farmed Fish and What to Eat

• Several commenters argue we should “just eat forage fish” (sardines, anchovies, sprats) directly instead of feeding them to farmed salmon, with bonus of lower mercury.
• Taste and texture are a major criticism of farmed salmon: often described as paler, mushier, fattier in the “wrong” way, and less flavorful than wild. Others report the opposite experience or prefer consistent premium farmed lines.
• Farmed shrimp from low‑regulation countries described as heavily polluting and poorly managed; one inland Spanish shrimp farm is discussed as a technical curiosity.
• Some see farmed fish (especially in regulated regions) as relatively low‑GHG protein; others call it “garbage” in practice due to antibiotics, feed quality, and ecosystem impacts.

Aquaculture Practices, Policy, and Certification

• Core problem framed as “how we farm” more than the concept itself: sea‑lice spread, chemical treatments, pollution, and feedback loops harming wild stocks.
• Chinese distant‑water fleets provoke a heated subthread: one side calls them de facto “acts of war”; the other stresses they mostly fish in international waters under existing law and are not uniquely bad compared to other nations’ fleets.
• Best Aquaculture Practices (BAP) mentioned as a certification system trying to tighten standards for farms and feed mills over time.

Alternatives and Future Directions

• Environmental NGOs criticized for saying only what not to do; defenders list actions like documenting illegal fishing and promoting gear/method changes.
• Some advocate drastically reducing or eliminating seafood consumption; others say this is unrealistic and argue for “harm reduction” via better species and production choices.
• Lab‑grown/cultivated salmon is described as promising but currently expensive, with open questions about feed inputs and scalability.
• Insects for feed (especially black soldier fly larvae) seen as low‑tech, already‑workable for certain species (trout, chickens).
• Oysters and other farmed shellfish praised as net water cleaners and ecologically positive; others argue they’re overpriced, overhyped “poor man’s food turned luxury.”