You don't
make any fish breed... that isn't possible.
Goldfish are near impossible to sex, and 49 gallons isn't very large for
Goldfish. Chances are likely that they would die before they'd breed in a tank of that size.
Goldfish take time to mature, which means they grow.... and to find a "pair" of
Goldfish, you'd have to keep a large number of them and let them pair off naturally. Mature, healthy
Goldfish, if in a clean and cool enough environment, will do everything on their own. Spawning is an instinct... and conditions will trigger those instints.
What kind of
Goldfish are they? (fan tails or comets)
Breeding habits in the different types of
Goldfish will be different.
I appreciated the "funny" and "cute" answers posted to this thread, and I understand why... because the original question inspires it.... but I do feel that the actual question should have been addressed by someone, even if alongside of the funnies!