Bumps On Engineer Goby

[Donya]

My engineer goby has turned up today with two bumps behind its head, somewhat on the back near where the pectoral fins are. The bumps are fairly round, but aren't raw or discolored. They're just, well...bumps. Tank stats are the same as usual: 0 on NH4/NO2, NO3<10 (near zero now because of macro), pH=8.2-8.4, sg=~1.025. I was tempted to attribute the appearance of the bumps to the fact that the fish has had a growth spurt and has suddenly become just a little too wide for a favorite hole in the rocks. More than once in the last week I've seen the goby stuck (right about where the bumps are) trying to force through. I did purchase and introduce some macro a few weeks ago, which is the only thing that has changed in the tank, so it occured to me that there is a remote possibility that something could have come in. I washed and somewhat scrubbed the macro multiple times in clean saltwater prior to introducing it, so I would think it unlikely that I brought in anything bad from the water. Still, I want to know if I should be worried about these bumps being anything other than bruises from trying to squeeze between rocks?

 

[SkiFletch]

Indescriminate bumps are a hard one to diagnose . Could be bruising as you say. Also COULD (although unlikely) be a tumor. Fish can get them too, not just people. Wish I had more to contribute. Got any pics?

 

[Donya]

Thanks Ski. I'll try to get some pics tonight or tomorrow, although it will be difficult. As soon as my presence is detected the goby is either under a rock or slithering around frantically trying to get under a rock.

 

[Donya]

Gwah...I think clear pics will be impossible. Best luck I had today was after I put the magnet in and was able to use the goby's curiosity against him and get a shot from the top where he couldn't see the camera. The good news is that there's now only one bump, and it has gone down a bit. Hasn't gone away fully though. For what it's worth:

(not that a circle around something that's barely visible anyway will help much I suppose )

Since the other bump is now gone, I'm keeping my fingers crossed that the other one will eventually dissappear.

 

[SkiFletch]

Tough shot indeed. Can't offer much more advice though . Glad they seem to be on the out though...

 

[Donya]

The bump on the back is still there, although somewhat smaller, but now the darned fish has turned up this week with a brand new, royal goose egg on the top of its head. I wish I could figure out how its managing to get these...wondering if I need to wedge the rocks better or something. Some of the smaller rocks can wiggle a bit, but aren't in a position to fall or cause anything else to fall. The goby's behavior has changed a bit too. It's still eating just fine, but not wanting to go under any rocks all of a sudden. In the last few days it's also started rubbing its head all over my sea hare. I figure there's probably a correlation between not wanting to go under rocks and having a bump on the top of the head (although the thing with the sea hare seems just plain weird), but I just can't see any way that it would have had a rock do that. Could there be any significance in behavior its doing with the sea hare? The goby isn't scratching or rubbing itself on anything else in the tank that I've seen.

 

[seffieuk]

Interesting you mention cancer tumours Ski, i'm sure I read somewhere that Sea hares excrete a poison that is being used in trials for some cancers - could it be the fish knows this instinctively (if there is such a word) and if so, wow

Seffie x

 

[Donya]

I think the behavior may be something to do with the sea hare's slime? I'd have to find a reference to see what kind of stuff goes into sea hare slime, but, being a frequent handler of gastropods (both fresh & marine), sea hare slime is pretty thick compared to what some other gastropdos produce. The fish isn't doing the behavior with any of the other gastropods in the tank and is still going at it periodically; at least the sea hare doesn't seem to care. The big goose egg on the head seems to be <1/2 the size it was previously now. The one on the back is still the same size. Keeping my fingers crossed that it goes away and no more show up.

I'm also wondering if these bumps could have anything to do with the urchin I've got in the tank. It's a Eucidaris metularia, never had issues with it before (besides it trying to munch my hand) but since I took the tank temperature down slowly from 78-80 to 72 it's had a growth spurt and is nearing 2x the size it used to be. Urchine bites? It does tend to share caves in the rock with the goby. It's starting to drive me nuts that I can't really find a better explanation for the cause of the bumps.