If you compromise your principles to make a buck, you will do it in other aspects of running a business and in dealing with individuals
I disagree with you there.
Where I used to work we worked hard to try and give what we felt was good advice and tried very hard to make our customers sucessful in the hobby, in addition to treating them fairly and with respect.
but we still sold parrots
just because you choose to sell a hybrid fish that is popular does not mean that you are going to scam your customers or in any way treat them worse than you would had you decided not to sell such fish.
Remember: you can be totally honest with your customers:
tell them its a hybrid and tell them that they are hormoned in order to breed.
then, they decide whether or not they want to buy the fish.
just be honest with them. Let them make the choice.
Because, to be honest, not selling blood parrots in todays market is not the best way to run a LFS at the moment.
they are popular fish and keep customers coming into your store, and thus keeping your store in business.