Basics
Can vegans eat fish?
Short answer
No, despite the popular belief that 'fish is not meat'. Fish have a developed nervous system and feel pain and stress, so ethically veganism makes no exception here. People who eat fish but not the meat of land animals are pescatarians — a different diet category, often confused with veganism.
The vegan definition has no “fish is not meat” exception. Everyday language sometimes mixes them up. Pescetarianism is a separate label — and that is fine; it is simply a different practice.
Vegans get omega-3 from ALA (flax, chia, walnuts) and from algal oil, not from salmon.