Foxface tail fin getting smaller

[rtzx9r]

Hi,I have a medium (4-5") Foxface who has been in my tank approx 6 months. He is very active, eats, and gets along with everyone well. However, his tail fin seems to be getting nipped or is rotting away (not sure). I never see anyone nip at him, so I just want to see what it could be.
Tank:
60 gallon reef
4 110W VHO bulbs (on 6 hours/day)
Arctica chiller @ 77/78 daily
Euroreef skimmer RS150
2 Korelia 3's in tank for circulation
sump/recirculation at aprox 500 gallon/hour (think, not certain)
100lbs live rock
40 lbs live sand
Inhabitants:
Leather corals (10 pound rock covered)
2 rose tip bubble anem (1 size of softball, other size of raquetball)
2 false perculia (2-3" each)
Scissortail goby (3")
6 Emerald Crabs
2 peppermint shrimp
pygmy angel (3")
Niger Trigger (3-4")
Foxface (6")
Mushrooms (large rock covered)
pulsing xenia (perhaps 100 heads)
Tank Params
pH = 8.2
Alk = 9 (working on raising!!)
Calcium = 400
Salinity = 1.024
Ammonia = 0
Nitrate = <10
Nitrite = 0
Food
daily minimal handful of dried food OR frozen spirulina
weekly (maybe 1-2x week) sheet of dried seaweed

 

[fau8]

I think your trigger is night time feeding.

 

[nanomantis]

You caught the victim and the culprit in the same picture.

 

[fishkid13]

Originally Posted by NanoMantis
http:///forum/post/3066937
You caught the victim and the culprit in the same picture.
+1

 

[rtzx9r]

Hmmm, maybe it is time to place my Trigger into my new 12 gallon nano cube - is that big enough?

 

[reefaholic33]

Yep I bet it's the Niger....and he will get worse. Mine was good for awhile but would never let me add any new fish.