Is eating seafood very often ok?

http://www.fda.gov/food/foodsafety/product-specificinformation/seafood/foodbornepathogenscontaminants/methylmercury/ucm115662.htm

By following these 3 recommendations for selecting and eating fish or shellfish, women and young children will receive the benefits of eating fish and shellfish and be confident that they have reduced their exposure to the harmful effects of mercury.

1. Do not eat Shark, Swordfish, King Mackerel, or Tilefish because they contain high levels of mercury.

2. Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish.
Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week.

3. Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.

http://www.scientificamerican.com/article.cfm?id=farm-raised-fish-not-free-mercury-pcb-dioxin

"Farm-raised fish may have somewhat less exposure to mercury than their wild free-foraging cousins because they are usually fed a controlled diet, often consisting of more grains and soy, a cheaper and more abundant source of calories, than fishmeal. But they can still absorb mercury, since most fish farms are themselves located in the ocean, just close to or abutting the shoreline.

Farmed fish can also absorb PCBs and dioxins, as the near-shore waters they occupy are the first stop for run-off from land-based sources of pollution. And the fact that their primary feed source comes from conventionally grown terrestrial crops means that their diets can include trace amounts of pesticides and herbicides as well. Also, most farmed fish are exposed to dose after dose of antibiotics to keep diseases and pests at bay in their crowded underwater pens, much in the way “factory farmed” land animals are drugged to help them cope with cramped, unsanitary conditions. In fact, studies have shown that farm-raised fish have more toxins overall than their wild-caught cousins, though exceptions of course do exist."

Bottom line, I would try to stay within the FDA guideline of 12 oz for either farm or wild.

hmmmmmm.. i eat a can of tuna, AND usually a tin of kipper per day.. this kinda worries me.. should i stop that? haha
thing is, these types of fish are a huge source of protein in my daily meals.. =/