When it comes to deciding whether to eat farmed salmon, the choice is not always clear cut.

Sure, farmed salmon in general gets a bad rap — and deservedly so. The Environmental Defense Fund issued a health advisory for farmed salmon because of high levels of PCBs. It takes  about three or four pounds of wild feeder fish to grow one pound of farmed salmon. Waste from open-water pens pollutes surrounding ocean waters. And the farmed fish can sometimes escape, posing potential problems for wild fish populations that can be affected by their parasites or diseases.

U.S. farmed freshwater coho salmon, though, gets a “Best Choice” recommendation from the Monterey Bay Aquarium’s “Seafood Watch” guide because it is farmed in inland tanks, lessening the potential spread of disease and pollution. They also require less wild feeder fish to grow.

Some chefs also favor a Scottish salmon, marketed as Loch Duart, which is farmed in the waters off the northwest coast of Sutherland. It’s billed as a sustainable alternative, but it, too, relies on feed made of fish meal and oil.

Now, into the fray comes a new farmed salmon, this one from the waters of Patagonia, Chile.

Known as Verlasso Salmon, this new farmed Atlantic salmon just launched last summer and is starting to show up in markets nationwide. Berkeley Bowl, which started carrying it in February, is the only retailer in the Bay Area selling it so far. You can find it at the seafood counter at both of its Berkeley stores for $14.80 per pound.

What makes this farmed salmon different?

Instead of needing three or four pounds of wild feeder fish to grow one pound of farmed salmon, Verlasso has developed a process to get that down to a one-to-one ratio. How? By supplementing the fish meal  feed with a special kind of yeast that is rich in omega 3s, which salmon typically get from ingesting other fish. In the future, the company hopes to get that ratio down even more, so that the farmed salmon can be raised with little to no fish meal at all, says Scott Nichols, director of  the Delaware-based Verlasso.

Read more