Ok wow those are really blurry, would you be able to get a more clear one if the sick fish? I know they move a lot, but if you could sit there for a few moments, you could probably take a good one. Right now, I can see he's obviously underweight. I cannot clearly see the body detail, so it would be impossible for me to identify any fungi or bacterial infections present externally. In observing what you provided so far, I can only make a guess as to what it might be, and keep in mind that without a really clear photo (closer also) there could be a lot of conditions that I cannot cover at this time simply because, well LOL I can't see the fish clearly. Right now though, at least as a starting point, tell me what YOU see since the fish is infront of you. Other than weight loss, reply with a list of these symptoms IF ANY are present. Only include ones which match your fish's condition, that you can clearly see ok. This is process of elimination here!
** Shredded appearance (even if only slightly) on ANY of the fins. May appear white on the edges, or slightly fuzzy looking.
**Excessive Jumping
**Red/swollen looking flared gills
**Flighty behavior (basically freaked out by everything, short random bursts of swimming, etc.)
**Any white spots present on body or fins (no matter what size the "dots" are)
**Fuzzy patches of any color (White, mottled, black, yellow etc.)
**Scratching/Flashing on substrate or tank decorations
**Any "stringy" things comming out from the anus, gills, around eyes, or on any other part of the body
**Any scales raised or irritated looking (think 'pinecone' in appearance)
**Any abrasions, bumps, boils, injuries, missing scales etc.
** Enlarged eyes
**Irregular swim patterns (quick swimming, stopping, drifting with currents, flickering, bumping into - or allowing currents to push into walls or decorations) - - look for patterns.
*NOTE - This is just some of the symptoms. These are the more obvious ones to an untrained eye, and should be easiest to observe. BUT if you notice anything about your fish not on this list, that is not normal in appearance or behavior, please add it in your reply!!! Let me know a.s.a.p! And I will hope for those new pictures soon! Good luck!
-Emi