yeah it was some longfin serpae tetras or my other betta [both from the same place] =[
luckily it only got a hold of my new tank and some rummys from my 10g, and i didnt lose my whole tank!
im going to treat the tank this weekend and sort out the nets, im going to buy one for each tank to stop cross contamination to!
aye i didnt beacause at work we quarantine them until they are fit to sell, i just naively presumed that this lfs did too =[
here to a better next time!