Jonah started with 14 fish + 2 more = <<14+2=16>>16 fish.
Of the 16 fish – 6 were eaten – 2 were returned to the store = 8 fish.
After he returned the fish to the store, he exchanged them for 3 new fish + 8 fish that were left = <<3+8=11>>11 fish now in his tank.
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