Was it murder!?!

[Yellow Hat]

Last night I came home from work to find my new yellow watchman gobie ripped open dead and being picked over by my peppermint shrimp. I don't know if it was killed or died of natural causes. Here's the history, if anyone has a guess I'd like to hear it.

Two weeks I bought the gobie and introduced it to my tank. He seemed fine, even picked a little cave right in front view on the tank. He basically stayed in his little 6 inch radius space.

One week ago my bubble tip anemonie died (it had wandered loose and twisted in a knot, again while I was at work this time I couldn't save it). I did a quick water change and tested the conditions. Ammonia was 0 and so was nitrite. Nitrate was at 10 ppm. But after that, the gobie seemed to be breathing rapidly, which he wasn't doing before.

The day he died he was swimming all over the tank instead of his usual territory. Not spaztically, but rather swimming slowly from one rock perch to another. Still breathing rapidly, though.

Now, I have an emerald crab that is as large in diameter as a half-dollar coin (if not larger). While he is not usually aggressive, he does have a favorite spot that he protects. I have two clown fish that the crab leaves alone.

This brings about the question.....did the gobie die because of natural causes (or tank conditions)? Or could the crab possibly have done it? It makes a huge difference because if I want any new fish I might need to remove the crab.

Sorry for the long post. Any ideas?????

 

[Sk8r]

It wouldn't be the first run-in between those two species: the ywg knows no fear and the crab has pincers that can crush coralline. I wish like anything I could figure out how to get rid my emerald crab. My ymg is my favorite.

 

[Angel*Fish]

Sad story

I've heard so much bad stuff about crabs, I refuse to own one. Can you just remove the rock he's on? Try holding a net underneath to catch him if he jumps off (best with 2 people).

 

[ACBlinky]

The erratic swimming and breathing hard sound suspicious to me. It could be that the anemone released something toxic, or the goby may have already been sick when you brought him home - sometimes illnesses don't show up right away, and fish die mysteriously after seeming fine for ages. I'm guessing that the crab was just doing his job as part of the clean-up crew and taking advantage of a free meal after the goby died.

 

[stykthyn]

I agree with ACBlinky, but I would remove the emerald crab. when they get large enough they are know to eat healthy fish in their sleep.

 

[RichConley]

<a href=showthread.php?s=&postid=7301007#post7301007 target=_blank>Originally posted</a> by stykthyn
I agree with ACBlinky, but I would remove the emerald crab. when they get large enough they are know to eat healthy fish in their sleep.

Mine is the size of my palm, and doesnt bother any of my fish, even small fish that sleep in the rocks.


This is definitely a case of the fish dying of other causes, and the crab getting blamed. (and I think a lot of emerald crab issues are)

The fact that he had a BTA wander around and die (bad tank conditions, bta dying makes worse) and then the fish starts swimming around erratically, means it was disease/stress/whatever, and had nothing to do with the crab.

 

[technoshaman]

Sounds like the fish was sick / stressed from BTA death and then expired. YWGs are VERY hardy in my experience. I have a pair that I've had for 5 + years now when I got back into saltwater after a extended hiatus. They are durable, disease resistant fish and are not as flighty as other shrimp gobies ime. I still don't trust crabs but I doubt he was the culprit here.

 

[Angel*Fish]

<a href=showthread.php?s=&postid=7301819#post7301819 target=_blank>Originally posted</a> by RichConley
Mine is the size of my palm, and doesnt bother any of my fish, even small fish that sleep in the rocks.


This is definitely a case of the fish dying of other causes, and the crab getting blamed. (and I think a lot of emerald crab issues are)

The fact that he had a BTA wander around and die (bad tank conditions, bta dying makes worse) and then the fish starts swimming around erratically, means it was disease/stress/whatever, and had nothing to do with the crab.

The fact that it was a "new" fish supports RichConley's post. But there is no saying that the fish being new didn't also make it more susceptible & interesting to the crab.

Crabs are not brittle stars, but back when everybody thought green brittle stars were just harmless scavengers, I was always told that the reason he had eaten the fish was simply that it died of some other cause & he was just "cleaning" my tank

Also a it's possible the crab pinched your fish leading to an infection which killed him. It's possible the crab was harassing him & that combined with the stresses of being the new fish caused him to succumb to parasites/bacteria whatever his immune system might otherwise have dealt with.

(bad tank conditions

Anemones are sensitive to many things that wouldn't bother a fish at all - FWIW I did have a BT anemone go thru a power head one night. He was blenderized & the tank was so cloudy that visibilty was only several inches. Only obvious stress was the corals - fish seemed fine. That's just one case though -