Hello, Please help! About a month ago, I purchased a beautiful male betta. He lived his first few weeks in a 2.5 gallon tank, where he swam around gracefully. Just recently, I moved him into a 10 gallon tank which is divided. He shares it with a baby female betta. Just a few days ago, I noticed this gray spot on his left gill. The next day, it moved to his right gill and it looks like it's lining the outer flap of his gills. He is also lethargic. Not extremely, but he mostly just lays around in his glass jar or on the floor leaning next to the divider. He usually stays at the bottom except for feeding time or when something spooks him. The baby is acting a bit lethargic, too. She usually stays at the top or in between the thermometer and the wall of the aquarium. I feed him a mix of frozen food like daphnia, bloodworms, brine shrimp, spirinula, romaine lettuce, plankton, etc. He refuses to eat flakes or pellets, even the day I got him. I treat the tank water with a daily dosage of Seachem Prime. This is because the tank is currently cycling and there are levels of ammonia present in the water. There are no nitrates or nitrites yet. The tank is heated and filtered. I also added some aquarium salt today to make him feel better. The tank also has plants and a nerite snail. Could this be fungus? Velvet? It doesn't look cottony, it looks more interior, like his whole gill is gray. Maybe it's old age, he looks kinda old. My other betta had a gray chin and he passed from columnaris. Don't tell me it's columnaris.. I can't handle any more deaths from terrible diseases. Should I turn up the temperature? Should I use a product like pimafix? Please help. I only got a picture of his left side, but imagine that metallic color lining the rest of his gill openings. There is also a pic of the baby which looks perfectly healthy. P.S. I also added some live gravel from a small fish shop a few miles away. After that, the gray gills thing started to happen. It had live bacteria in it and I bought it to help cycle my tank. Could this have cause the problem? :/ http://imgur.com/EJcrZs4 http://imgur.com/Mpb6Nbl Thanks.