Oh no my guppy has shredded finnage

My only guppy has a shredded at the end tail fin, he was fine the other day during pictures and now this..
Water parameters are all ok, Ate is at approx 8.0 PH 7.6 Ammo and Ite are at 0
Is this his tail growing at a different rate? I dont' see any cottony growth or anything untoward he is acting normal..
Everyone else looks fine (no other guppies) Never noticed anyone nipping at him...
I have a picture it makes it look worse as it's streaking as he's moving..


Could this be contagious? I've had him ages and never a problem... no recent fish introductions into the tank....

Neon Tetra
3 Silver Dollars
cory cats
harlequin rasbora
dwarf gourami

The guppy is the most outgoing member of the tank the one with the most ba**s for doing his own thing a real gad about.. The other fish dont' bother him at all I have witnessed him chasing the neons when there is a pea or small food item he is interested in.