little guy x x xhave you done a test and a water change to try to establish what killed him ? its a shame and im sure you wouldnt want it to happen again,so if it was nitrite/ammonia you must do a test and get it sorted out, it may have been natural tho,i used to find them dead in my filter when i first started fish keeping, but something must be making him weak enough not to be able to swim away, ie, illness water condition
shelagh xxlittle guy x x x