Combine water, 1/2 lemon juice, parsley, salt, and pepper in a large, deep skillet.

Add the fish fillets in a single layer.

Bring the liquid to a boil, then reduce heat and cover the skillet.

Simmer for 5-10 minutes, until fish is cooked through but not falling apart. Turn fillets carefully if thick.

Transfer fish to a serving dish using a slotted spoon and reserve the broth.

Beat eggs and 1 lemon juice in a medium bowl.

Mix matzo meal and water in a small bowl to create a creamy paste.

Stir the matzo meal paste into the egg-lemon mixture.

Gradually stir in about 1/2 cup of the hot fish broth into the egg-lemon mixture.

Pour the egg-lemon mixture back into the remaining hot fish broth.

Stir over low heat until the sauce thickens.

Adjust seasoning if needed.

Pour the sauce over the fish.

Serve hot or chilled.