[Mattfish]

It turns out now that I must have an aggressive fish. In a thread a few days ago, I mentioned by dead Banggai. Today before feeding, the other one was just fine. After feeding, he was dead and floating around. I didn't see anything happen.

I also noticed our little Royal Gramma hasn't been seen for a few days either. And a Clown Goby that we got a week ago disappeared immediately and was never seen again. At the time, we figured he was so small, and was just hiding in corals like they do, but after a week, he's also likely gone and could have also been a victim.

It seems clear that there's a predator, and my thought is that it may be the Midas Blenny. The Scott Michael Marine Fishes book mentions Midas' as possibly tearing the fins of firefish and gobies. He's relatively new in the tank, but the cardinals and clown goby came in after him. The Gramma was there before...

It's also possible but less likely that it's the Arc-Eye Hawkfish. He's always been well behaved and is one of our long-timers - he's been fine while away when we redid the tank, but the cardinals, and clown goby came in after him, and again, the gramma before.


Besides keeping an eye out for clear acts of aggression, or possibly trying to remove either or both, any good ways to determine the aggressor? I'm not even sure who the culprit would still go after - possibly the bicolor blenny but not sure who else. Do I just sit and wait or is there a better plan?

[glampka]

Grab a chair, some coffee to keep you awake & start watching each & every fish!!!

[david6789]

HAve you checked for Mantis Shrimp? Evil little buggers!

[Jeremy0322]

I was thinking mantis as well...

[Mattfish]

Originally Posted by glampka

Grab a chair, some coffee to keep you awake & start watching each & every fish!!!

That's what I thought... Starbuck's here I come...

Originally Posted by david6789

HAve you checked for Mantis Shrimp? Evil little buggers!

No, but I've eaten quite a few....

[pogodzib]

If you have a mantis, you probably would have heard it popping by now and would have been asking about the noise. It could be either a mean fish or because your tank hasn't had time to finish its cycle and stabilize yet. I'd recommend doing a 20% water change if you haven't done one within the past couple days to get your nitrites down and then grab the chair to watch your fish. Just make sure that you're far enough away from the tank so that all of the fish act normally and aren't scared with you being there watching them.

[Mattfish]

Nitrites happily 0 and the crew will come tomorrow to change out 20-25 gallons.... I'm off to get glasses - never needed them before - so now Ill be able to watch and see what happens...

I'll bet it's the Midas Blenny though.... He hangs out at that end of the tank....

[pogodzib]

Glad to hear that the nitrites are at 0 now. Now just sit back and enjoy your tank while trying to figure out the culprit.

[rlcline76]

How many new fish did you add. Could be one of the veterans stressing out with the move and quick parameter spikes. Hell, I have a cat that doesn't like moving from house to house, craps on the floor, ticks me off. Could be a new guy. If you hear any snapping in your tank, you might have a nifty predator. My advice is the same as Gary for the fish and the cat: night vision goggles, coffee and a pellet gun.

[Fishhead Junkie]

i have a starry blenny and he kicked the living crap outta a lawnmower blenny i added. when i say kicked the living crap..i mean, HE KILLED HIM...it was like watching THE TERMINATOR VERSUS SARAH CONNER...this time, the terminator won!!! he never has touched another fish in the tank..he'll even let my coral banded shrimp grab him with its pinchers and i dont think they are playing either. good luck though..i would set up a camcorder on a tripod and see what you find out. cant hurt.

steve

[rlcline76]

Like Nanny cam

[Mattfish]

Everything seems to have settled down. No new losses, no new additions. I'm guessing it's a natural fish-shape or predatory thing. The book said Midas Belnnies were prone to this, and even though he was the new guy, he seemed to take over.

Anyway, I did get the night vision goggles and pellet gun, but had to go to sleep early last night. Maybe I'll try to stand late watch tonight and discover the underhanded culprit! Or, more likely, fall lazily asleep again.... That works too....

[Jay03GT]

I had a blenny that took a dislike to my clownfish pair. After about a week the female clown must have got tired of it and they fought it out during the day when nobody was home. Ended up loosing both the female clown and the blenny.