Sick Zebra Loach?

[stevenufc]

i have four zebra loaches one of which has developed a black face is this anything to worry about?

other than that the behaviour is normal water parameters are ok etc


http/i175.photobucket.com/albums/w160/st...fc/DSC00140.jpg

 

[WILDER]

Need to look at your water stats.
Is there some fluffyiness there to it as I can see some.
Black patcches, ammonia burns that are healing, some fish can get patches through digging.