Sorry to see this from a vendor. They should know better than to ship pretty much ANY central American species larger than 1-1.5" in the same bag together if they wanted them to arrive intact. Typically by 2" most CA species are capable of taking each other out in the small confines of a bag. If they don't kill each other then for sure they will tear each others fins apart. Poor shipping method. Also, T. ellioti is not a valid species which the vendor should know. They haven't been valid for over 20 years. These will be Thorichthys maculipinnis.
the recommended meds everyone mentioned should fix the fin issue if it is indeed a disease and not just torn up from the other fish during shipping. My go to meds here are a malachite green & formalin combo, with Nitrofurazone and rock salt all at same time. Since the vendor already has them ID wrong and shipped them terribly you might as well add general cure for peace of mind. good luck!
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