What does this rock pool fish eat? It looks like a Goby!?

[Andrew R]

I went to the beach yesterday and caught some little star fish in the rock pools. I left a cup in some water in the rock pool and a few other critters crawled in.
I didn't notice that I caught a fish and it was well camouflaged. I knew what all the other critters ate but not the fish.

The fish jumps a lot, it stays on the bottom of the tank, it has a strange long anal fin which act like swimmerlets on shrimp and its is a long fish.
I thought it looked a bit like a mud skipper but I searched them up and found Gobies. The fish looks a lot like a goby and thats what I think it is.
The anal fin puzzles me. I couldn't see the strange anal fin on the goby images.

 

[Trollkepr]

I would start out with some live brine shrimp and some flake food. The brine shrimp are not the best as fas as nutrition. Hopefully they will eat the brine shrimp.

If it only feeds on live food, You may have to raise up the food. There are a lot of types of food you can raise. Gust look it up.

 

[galanorthevampiress]

Hmmm... It would help if you had pictures of the little guy. I could better identify it if you did... does it seem eel-like? If so, you probably have a cusk eel, or a similar species. They can get quite large, so unless you have a pretty big tank, I would suggest letting him go. Then again, I can't assess it properly without the right identification; it could be something else altogether. They are generally carnivorous, and feed on inverts like shrimp when they are young and in the wild. In captivity, you could try some sinking pellet foods, but they prefer live over manmade.

EDIT: Where do you live, exaclty? Where you are affects what species you are likely to come across.