so i revamped my tank today, taking out the majority of fish and placing them in a bucket. my little girl was hangin around harrassin them, i turned round and noticed Jaws(silver shark) about a metre away from bucket,on floor, rolled in fluff!!(think he was kicked by my little girl, by accident) his gills were closed so i thought he was dead. then i thought id give him a go, so i put him in the water and opened his gill with my finger nail(only way i could think)then as if by magic he started to breathe again!! so i held him for a minute or 2 then let him go. he was upside down floating on surface but still breathin. i held him again a bit longer, and an hour later hes back in the tank swimming around, happy as larry!! must have more than 1 life. hurray for Jaws!