Eviota gobies, dither fish?

[Anonymous]

Okay, so last week I was lucky enough to find some threadfin cardinals (apogon leptacanthus) from an online vendor. I've got five of them, and they were intended to be the only fish in my 40 gallon.

Thing is, bold they are not. They've spent the last three days in a very tight school almost exclusively in the same 4" x 4" x 4" area of the tank, not even venturing out of it to feed. They'll grab any food that comes near them, but if it's even a few inches away they won't go for it. I've been running the tank with actinics only since I got them, but not even the combination of subdued lighting and live food has encouraged them to venture out of their little spot.

So now I'm thinking of adding some small dither fish. I came across a couple of species of eviota gobies listed at liveaquaria that are described as "very active". Anyone have any thoughts on them as dither fish? Any special concerns or needs where they're concerned?

 

[Anonymous]

CJ,
I wouldn't be surprised if your cardinals considered the Eviotas as a highly nutritious snack. They are very very tiny. I had a clown goby eat one once, that's how small they are. Besides that, it is unlikely they would coerce the cardinals to be more active. They do quite a bit of hiding themselves.

Firefish and flasher wrasses make great dither fish. <shrug>

 

[Anonymous]

How about some fairy wrasse or a couple of small anthias or even a flame angel?

 

[Anonymous]

I had a clown goby eat one once, that's how small they are

8O 8O 8O

Damn - now that's tiny, alright.

As for the other suggestions, there are two things to take into account...
1. The tank is open topped, at least til I get around to having some sort of custom coverglass built. So jumpers are a worry.
2. When it comes to fish, I'm a chronic understocker. I'm already feeling edgy about having the five cardinals in a 40g, so any other fish that gets added I want to have minimal biomass.

In the end it might come down to a couple of chromis. I was just hoping to find an alternative.

 

[linderaberry]

Safety in numbers -- might the cardinals become bolder if they were more numerous? Would one or two more be too much biomass?

 

[Anonymous]

There's five already, so I'm not sure adding another couple would make much difference. But for that matter getting threadfin cardinals is difficult... no knowing when I might find some more.

The threadfins are gradually getting a bit bolder, going further away from 'home base' if it means they'll get food out of the deal. I'm hoping giving them a couple weeks will see them settle into more of the tank, we'll see.