So yesterday, Saturday 4/7, I picked up two new platties and added them by themselves to the 40 gallon tank along with a bottle of safe start. Today one of them is dead. All seemed OK this morning and I didn't notice him doing anything that seemed odd. Given I've only had him since yesterday that is, of course, relative. Just didn't notice anything that struck me as a red flag. He hung out, nibbled at the sand occasionally, but that's it. Thinking about it he didn't seem extremely lively but figured it was just due to the new tank. Neither has eaten much at feeding time, but I chalked that up to the stress of being moved to a new tank and figured it would resolve in a day or two. I went to my Uncles for about five hours and came home and he was just sitting dead on the bottom of the tank. Looking him over, there doesn't seem to be anything obvious that I am seeing on him. Again, have another and he seems fine as do the bunch of MTS in there, and they've been in there for a few days longer then the platties. Pics, one in the bag when he was acclimating and one taken post swimming off into the sunset. On the one where he is dead the white is just a reflection, there were no white spots on him. I'm leaning towards just bad luck, but being as it's the first fish I've lost just wanted to double check if there was anything about him I might be missing. Thoughts?