As far as I understand you have got to use the credit for the replacement fish. It is not transferable. Use your credit voucher, get the fish, trade it or sell it. That is the best you can do. I have a credit for a Pygmy Angel from Saltwaterfish.com, but I have a Coral Beauty in my tank. If someone wants a pygmy angel the next time I order I will use the voucher and obtain the fish for them.