Introduce goldfish to Lake Victoria and/or breed them to be euryhaline?

Goldfish originate from Asia but have been become an invasive species in North America:

Goldfish overrunning Minnesota lakes to become snacks for zoo animals

How massive, feral goldfish are threatening the Great Lakes ecosystem

If goldfish were introduced to Lake Victoria, they could be a food source for Nile Perch and thus take pressure off cichlid fish. 

And if goldfish could be conditioned to saltwater, they could be a food source for tuna and swordfish.

Lionfish have been successfully conditioned to freshwater.

Sixth grader credited with scientific breakthrough on lionfish