Pale, Agressive Yellow Coral Goby

[matthewpunger]

Hi there,

I was hoping somebody could help me, I've been searching on the net for a while trying to figure out what's wrong with the little guy, but not much luck...first here's my tank:

10g nano-reef - 5 months old
2 yellow coral gobies - food: brine shrimp, flake mix (they're picky)
1 yellow tailed damsel
1 camel shrimp
bunch of inverts
10lbs live rock, 15lbs substrate
xenia, polyps, mushrooms
2 coralife 50/50 10W bulbs, biowheel filter
regular water changes, salinity consistently 1.023

So the problem is the bigger goby is very pale and sometimes quite aggressive to its mate (i don't think they're a mated pair yet) and chases and nips at the little one. the pale one's color has been up and down for the past maybe three or four weeks. The damsel leaves them both alone and I feed them well with mixed frozen brine shrimp and new life spectrum flake food for added nutrients. I do a water change at least once a week and since he's been pale, maybe every 5 days. I'm guessing he's either stressed or going through a sex change which can't be that easy...

any ideas? thanks for any help,
Best,
Matt