Preheat grill to medium-high heat. Rub each piece lightly with canola oil.
Rub grates of the grill with a canola oiled paper towel. Place poblano pepper on grill and grill until blackened. Remove from grill and place in a paper or resealable plastic bag to rest. When pepper is cool enough to handle, peel off blackened skin. Remove the stem and scoop out the seeds. Chop only half of the pepper and place in a large bowl. Reserve the other half for another use or discard.
Arrange fruit on grill and let cook 2 to 3 minutes, turn over, and cook an additional 2 to 3 minutes. Remove from grill to a cutting board and let cool. When fruit is cool, chop into 1/2-inch pieces and add to the bowl with chopped poblano pepper.
In a medium bowl, combine the minced serrano pepper, cilantro, lime zest and juice, agave syrup, lemon juice, cayenne, cinnamon and salt. Mix well and pour over the grilled fruit. Gently stir to combine, cover and refrigerate for 30 minutes. Serve on top of fish.
Fish: Preheat grill or steel drum to medium-high. Rub the grill with a canola oiled paper towel. Salt and pepper both sides of fish. Gently place fish on grill or steel drum, cook for 3 minutes, carefully turn over and cook for 2 minutes more. Remove from heat to a cutting board, cover and let rest for 2 minutes. Cut into serving size pieces, if desired, and serve immediately with fruit salsa.