German Ram headstanding

lauraf

Superstar Fish
Jan 1, 2010
2,181
0
0
Vancouver, British Columbia
#1
Hi all:
I noticed today that my previously healthy male German ram is fluttering his fins like mad and swimming in the corner at a 45% downward angle. Everyone else looks fine, and I've had no recent illnesses or deaths in my tank. I read the link in the sticky and understand that this might be an air bladder issue? I have nowhere to isolate this fish, but have lowered the temp about 1.5 degrees C. Any other advice? Should I dose the whole tank with the erythromicin that was suggested in the sticky?
BTW, recent water tests (at home with liquid test kit) show pH just under 7.0, ammonia 0, nitrate a bit high at almost 50m/L (water change scheduled for tomorrow).