Clean fish (or fillets), cut into pieces. Sprinkle with salt. Let stand 1/2 hr. Drain and tinse fish. Place in saucepan with lemon and onion, cover with water, bring to wimmer; drain.
Arrange fish in glass container with some lemon and onion slices. Bring 3/4 c. water, vinegar, spice, sugar to boil. Pour over fish. Cool. Refridgerate 24 hours.