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1. Download a Monterey Bay Aquarium Seafood Watch pocket guide for best picks, fish to avoid, and good alternatives. Go to Mobile.SeafoodWatch.org for apps.

2. Text the word FISH and a species name to 30644; the Blue Ocean Institute will send a sustainability rating and better options.

3. Look for the Marine Stewardship Council label on wild-caught fish in stores and restaurants—it's the most rigorous certification there is.

Avoid These:

• Chilean sea bass (overfished)
• Orange roughy (overfished)
• Bluefin tuna (overfished, high mercury levels)
• Most farmed, imported shrimp (environmentally irresponsible farming)
• Most open-net farmed salmon (environmentally irresponsible farming)

Choose these:

• Tilapia, Central American farmed (Low in mercury and other contaminants, environmentally responsible farming)
• Catfish, U.S. farmed (Low in mercury and other contaminants, environmentally responsible farming)
• Rainbow trout, U.S. farmed (Low in mercury and other contaminants, environmentally responsible farming)
• Crab: Dungeness, stone, or kona (Low in mercury and other contaminants, sustainable fishery)
• Mussels (Low in mercury and other contaminants, environmentally responsible farming)
• Bay scallops, China farmed (Low in mercury and other contaminants, environmentally responsible farming)
• Fish caught with hook and line, traps, pots, or harpoon (Environmentally responsible farming)

Next: Got that? Here's what you need to know about buying meat