How many times can i eat farm raised salmon per week?

I have been on this salmon kick recently over the past few months. I get 1.5lbs of farm raised at whole foods or this little market by my house and i have been eating it in a week. i have the person cut it into 6 pieces so i am eating about (6) 4oz servings per week. is that approaching the unsafe side?

sidenote:
i workout 4-6 times per week and sauna if that affects anything i.e. ridding my body of mercury.

thanks