NEON TETRA shaking A LOT at the bottom. DEAD?

[fishingBuds]

Mt neon tetra JUST started with this behavior, im dosing the tank with melafix and today was "bloodworm day" so I dont know if he is over feed. I never had this issue with them, any issue tbh, and I follow this routine for a long time now.

I turned on my airstone 2 hours earlier today because of his behavior, i think it can be oxygenation? But how can the other neons and fish not be struggling?

I searched bout it and found out that can be over stress of its enviroment, could it be the 10 day medication the tank is on? Melafix isn't that strong so I dont think so, he is super fat and swimming ok but he is shaking and breathing heavily for 3 hours now.

RIGHT NOW all neon tetra are following the "sick" fish, as shown in the last picture. Thats super weird behavior because when fish are dying they usually go away from other fish and now they are schooling around the stressed fish.

Any advice on how to apot the issue or if my routine is wrong somehow???

Thank you very much for reading and participate.

 

[Delapool]

Fish ‘quivering in one spot’ (if I’m reading right) I’ve had from reaction to melafix/pimafix or from driftwood too green.

 

[fishingBuds]

Thats weird, cause its a fat neon, the biggest one I have. Also I have a lot of other fiah in the tank and all of them got cured and are good, but that neon is weird...super fat, deformation of its body lines, heavily breathing and shaking, at the bottom of the tank, while other neons swim around him. Looks like they are praying of something, like they know that neon is specifically different.

Fish ‘quivering in one spot’ (if I’m reading right) I’ve had from reaction to melafix/pimafix or from driftwood too green.