They were all sent in big bag, same as the other fish. Maybe they are more prone to have problems when shipped like that. If I buy any more cory, it will be in person.I don't know if the problem is becoming more prevalent but I've seen quite a few people suffer with possible shipping issues and I wonder if it's partly because postal costs have risen, so some suppliers are minimising the amount of weight by reducing water. Certainly here sellers that use royal mail, often keep weight down to the cost of the fish.
Were these fish sent in a large/adequate poly box or was it a bit of a squeeze?
Sometimes sellers also ship fish out that have only just recently arrived and multiple shipping stresses can really do some damage.
The five remaining were okay today, even the one that were not okay yesterday.
Pretty active and eating normally as a group, no signs of scratching or bad swimming. I hope they don't relapse.