yellow damselfish

[chamic1]

I got my yellow damselfish almost 3 weeks ago. i noticed a dark area on its head and only on the left side. Any idead what it might be?

 

[chamic1]

here is another pic

 

[chamic1]

Another and his tank mate that is normal

 

[chamic1]

Another question... Does my blenny look malnutritioned?

 

[chamic1]

Another of my scooter blenny

 

[beth]

Blenny does look pretty skinny. The lawnmower has a very specific herbivorous diet and, if your system can not provide him with that diet, then you will have a problem. The lownmower will frequently starve to death.
What are you feeding him, and is there enough algae in your tank to support him?
Yellow damsel is likely young fish coming of age.

 

[chamic1]

I currently feed my blenny blood worms, mysis shrimp and brine shrimp which are all frozen. I don't have any alage except for some that grows on the back glass; however, it is not very long and plentiful.

 

[beth]

chamic1, and that is the problem. This fish is an algae eater. He may eat other things, but those things do not provide him with the nutrition that he needs.
Try getting foods that are algae based and see if you can fatten him up. Also, do a search here for hobbyists with lawnmowers and see if can elicit some tips on feeding. I know there was someone recently who posted a lawnmower that was really fat.