Edited it myself. Was having a rough morning and vented in a poor way! I still feel he shouldn't have to pay shipping for the replacement though. You don't pay shipping twice if you receive a faulty item from someone. Fish should be no different. In my defense though, I did make sure not to post any names.
Im going to make a suggestion at the risk of getting in the middle of "none of my business". I can see the point on the shipping cost but also agree that if you knew, and you must have, the parameters of the deal then there is really no good argument for you to have. I would suggest a more softer approach to the company giving your thoughts and prior history with the company. Ask if they would consider credit beyond the value of the clam. Probably wont but hey thats the way I would like to hear it if I were them. Just a suggestion.