The two Goldfish eat a total of 2 * 1 = <<2*1=2>>2 teaspoons of food.
The 3 Swordtails eat a total of 3 * 2 = <<3*2=6>>6 teaspoons of food.
The 8 Guppies eat a total of 8 * 1/2 = <<8*1/2=4>>4 teaspoons of food.
In total, all of her fish eat 2 + 6 + 4 = <<2+6+4=12>>12 teaspoons of fish food.
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