This is the swollen double tail I had posted about before, where it seemed he had gotten ammonia burn along with fin rot. I had updated the thread because I had remembered he had gotten a seashell (direct from the ocean) put in the tank without it being cleaned properly first, but I didn't get a response about that.
Anyway, now it seems he definitely has dropsy; his belly had been a bit grey for a while and now his scales are definitely pineconing. I have been treating him with tetracycline for these weeks for the rot, which hasn't gotten better or worse. The pineconing is new though. At this point is there any hope of him getting better?
[I put him in a three gallon tank with a heater, the temp is always 78. I clean the water twice a week, 100% changes. He has been eating two pellets a day, but only if they are right in front of him - he has trouble swimming well and is listing to one side. I never tested the water]