What could have happened to my goby?

[Tuscaquatics]

On Thursday I bought a diamond sleeper goby for my 55 since I've been having problems with my sandbed. I acclimated him for a couple hours and put him in. He never ran to hide in the rockwork or anything like that. He swam right down to the sandbed and, within 5-10 minutes, was scooping and sifting sand like I had seen him do at the LFS. All in all it was the best experience I've had so far in acclimating a new fish.

All night Thursday and all day Friday he was fine, cleaning sand nonstop. In a day he had more than half the sandbed sparkling.

But on Saturday, I was watching the SEC Championship and I went to turn on the lights. When I did, I found him belly up at the bottom of the tank, dead as a doornail. He didn't have any signs of trauma that I could see.

My amm/trites/trates are at zero. pH 8.4 and temp. 78 steady. SG 1.026.

I'm wondering why a seemingly healthy fish would up and die like that so suddenly. One thing I've been thinking about is what was on the sand. Since I've been having trouble keeping the sand stirred, there has been a thin layer of what I guess is green cyano. As he sifted the sand, he seemed to be eating pretty much all of the green stuff. Could this have been bad for him? Maybe he was so hungry from being in the LFS tank that he got here and just went to town on something he shouldn't have eaten.

I also have a coral banded shrimp in the tank that I've been wondering about. But surely if he had anything to do with it, there would have been trauma to the goby, right?

I've had my share of trouble keeping tangs (it will be a while before I try with another) but aside from that, I think I've been doing a pretty good job. I never dreamed I would have this happen with a goby.

Anybody have any thoughts on this? Is cyano bad for fish? Would he eat something he shouldn't have?

 

[romsoccer12]

im pretty sure it wasnt the cyano or the CBS. tank size/sand depth? was he eating and looking fat at the LFS? maybe you should get a chromis just to test if there are any bad chemicals in your tank

 

[Tuscaquatics]

Yeah, he was sifting through the sand at the LFS. I'm sure he wasn't getting a ton to eat because their tanks aren't exactly teeming with life. But he looked healthy and pretty fat.

The tank is a standard 55 gallon. The sand is about 2-3 inches deep.

 

[IFbettas]

Just so you know, a 55 gallon tank won't be able to support a diamond goby for very long. They need a much bigger sand bed with lots of life in it. I put a diamond goby in a very well established 55 gallon tank that was crawling with worms and pods, and within 2 months there wasn't a single worm left in the sandbed. This was really bad, because they often don't accept prepared foods. He now is finally eating mysis and pellets and is fat again, but I would never buy one of these fish again unless I had a huge tank.

 

[romsoccer12]

+1, its honestly needs a HUGE sandbed teaming with foods! its like a mandarin but with sand.

 

[snorvich]

+1, its honestly needs a HUGE sandbed teaming with foods! its like a mandarin but with sand.

Yes, absolutely true. Normally they will deplete a sand bed rather quickly.

 

[Tuscaquatics]

Nobody managed to answer my question.

 

[Tuscaquatics]

What about the lunare wrasse? I know these guys can be mean. But mine is only about 2.5 inches right now and he doesn't bother the other fish. I'd be surprised if it were him.

When I bought the wrasse, I wasn't planning on getting one and I hadn't researched it properly. The guy at the LFS, who I thought was knowledgeable, said he would be reef safe. Since then he hasn't seemed to cause any problems, but I now know that once he gets big, he's definitely gonna be a problem in a 55g reef.

But do you think he's become a problem already? Wouldn't the goby have had visible trauma if the wrasse got to him?

I guess I'm gonna have to catch him and trade him in or something. I'm not looking forward to that after having already tore the tank down to catch a stupid damsel.

I'd love to get to the bottom of this. My tank's been going so well lately and, aside from my issues with tangs, I never thought I'd have a problem with a fish like a goby.

 

[IFbettas]

I doubt it's the wrasse. There are many possible reasons for why your goby died, but it would be impossible to tell without doing an autopsy on it.

As far as catching the wrasse, you shouldn't have to tear your tank down if you go about it smartly. Probably the easiest way to catch him would be to use a tiny barbless fishing hook and put a piece of mysis on it. When the wrasse goes for it hook him and pull him right out. Just try to make sure the fish doesn't swallow the hook, or you'll have a dead wrasse. If he does appear to swallow it don't try to pull it out, but rather put slack on the line and wait for the fish to spit it out. Good luck!