Made a big mistake! Too many goldfish!?

My cousin and i went to my town's festival, and he went off and won 4 goldfish, three orange ones and a white one. i felt bad for them in their filthy bags and let him put them into my 30 gallon tank with 3 dojo loaches. Crap. What do i do? should i force them back on him and tell him to deal with them? theyre small, about 1.5". i showed him research on google and made sure he doesnt play those games anymore, so 1 good thing came out of this. i have made tons of mistakes already, nd i dont want anymore fish to suffer at my hands :(