That seems reasonable to me that they are offering something. The one privately owned LFS near me offers no refund if a fish dies, its printed on their receipts. I guess they cant swallow the lose like a big box store can.
^^I agree^^
I try and support my LFS. They provide a good service and I normally will pay the high prices for the their fish because I know how tough it is for them to survive. I recently purchased two 4" chinese hi-fin loaches for $75 only to have them die three days later in a well established suitable tank. I had an understanding with the owner of the LFS that I could sell them back to him at cost if they outgrew my tank. In such a situation I would expect $75 credit from the store.....(I certainly don't expect my cash back). The store has no guarantees and has said it would 'work with me', am I being unreasonable to expect this full credit ?
A full credit or refund doesn't fix the issue of two fish dead....from the same store, at the same time, in your tank. Now, your tank is, I'm sure, just as you say, well established and healthy, but it doesn't mean that you keep your tank the same way the LFS keep theirs. Loaches are sensitive fish as it is and shocking them from an environment the are used to, to an environment totally foreign, would kill a lot of different fish...just from the stress alone.
Put yourself in the shop owners shoes for a minute. Just because you are a responsible fish keeper doesn't mean the majority of their customers are...if they refunded for every fish that dies, they would be out of business in no time...and sadly, many LFSs in my area have done just that because they aren't large corporate sponsored super pet stores.
My advice, for whatever it's worth, is take a sample of your water to the LFS in question and ask them to test it with their test equipment. Test your water first so you have a base line to go by. Then ask them to test their water and do a comparison. Note the temperature and possibly the salinity. ..many LFSs use salt...some keep their tanks on the warm side with ich meds constantly present.
Give a little and expect a little back...I am sure they have no intentions of selling sick fish...this is their livelihood....don't go in there all demanding and irritated, who want to help that guy?
My opinion may sound preachy, but I have been on both sides and I know this situation well.