my koi recently lost 4 of its scales
, i think it was from it trying to squeeze past the strainer thats at the end of the pipe on my filter. i removed it last night. before i removed it my fish had 3 scales missing, i have no clue as to how the 4th one came off. is this a natural thing for a young koi to lose its scale as it grows or should i be worried. i monitored it closely last night but it showed no sign of illness.