Baby Fish ID

[Dog Whiskey]

Looking for some help. I have a 55 gallon FOWLR. Introduced three blue-green chromis in late December who within a week became two blue-green chromis. The bully was then sent into a breeder box for a couple of weeks.
I also have a pair of juvenile clownfish (introduced in mid-January) who are still trying to sort out their hierarchy.
Mid February I introduced three fish from @Biota_Marine: a radial filefish, a starry goby, and a forktail blenny. I've also introduced some snails and some macro algae and copepods from @AlgaeBarn
So today this dude shows up. NO ONE has demonstrated any spawning behavior. He's about 1/2 inch, blends with the rocks, and appears to be a fish. His dorsal fin is kind of in the position where it would be for a chromis, but the body is less chunky and more elongated.
Any ideas?

 

[Sharkbait19]

Was this live rock? Where from?
My money is on it being a hitchhiker that didn’t show up until now.

 

[monkeyCmonkeyDo]

Cardinal?
D

 

[Dog Whiskey]

Oooh a Cardinal would be cool! It was live rock from a local fish store, but they keep their live rock all in a tank without fish.. supposedly...

 

[PeterEde]

Oooh a Cardinal would be cool! It was live rock from a local fish store, but they keep their live rock all in a tank without fish.. supposedly...

but were eggs already on the rock?

 

[Dog Whiskey]

but were eggs already on the rock?

Not to my knowledge. And most of the rocks went through the whole ammonia phase so I can't imagine eggs would survive.

My guess is it's a hitchhiker of some sort, but I can't figure out where it could have come from. I know it wasn't visibly with any of the CUC or the fish I got from Biota and Algae Barn's macro is from a clean facility.

 

[bnord]

A little guy like that could have been in a hidey hole for quite some time -
break out the copepods...

 

[PeterEde]

Not to my knowledge. And most of the rocks went through the whole ammonia phase so I can't imagine eggs would survive.

My guess is it's a hitchhiker of some sort, but I can't figure out where it could have come from. I know it wasn't visibly with any of the CUC or the fish I got from Biota and Algae Barn's macro is from a clean facility.

The Jesus fish.

 

[vetteguy53081]

Looks like a gambusia which is a livebearer and would live in saltwater

 

[Dog Whiskey]

Looks like a gambusia which is a livebearer and would live in saltwater

That's a possibility, but it appears the anal fin is tighter to the tail than on the gambusia photos I'm seeing. And if a live bearer hitchhiked on live rock could it survive the cycle after being dosed with ammonia?

 

[PeterEde]

Maybe someone is playing a trick and dropped it in?

 

[Dog Whiskey]

Maybe someone is playing a trick and dropped it in?

It must be the cats!

 

[minus9]

The eye position and mouth remind me of a perchlet/hamlet, but also has some cardinal traits in there as well. Keep us posted as it grows. Fun stuff!

 

[HudsonReefer2.0]

 

[rmorris_14]

Following! little fishy..

 

[Dog Whiskey]

I wish I could get a better picture but it's SO tiny and sticking to the rocks for the most part. It did get brave and venture out into the open water, but when it saw the camera it darted back to the rocks!

 

[rmorris_14]

last GIF...for now....

 

[Seymo44]

I live on the Back Bay in Biloxi, MS. We have sail-fin mollies in brackish ditches and bayous around here. That looks like a baby. They’re live bearers and live in full fresh or full salt water. They are not as colorful as the ones at the LFS, but the males do have lots of color on their fins.

 

[minus9]

I live on the Back Bay in Biloxi, MS. We have sail-fin mollies in brackish ditches and bayous around here. That looks like a baby. They’re live bearers and live in full fresh or full salt water. They are not as colorful as the ones at the LFS, but the males do have lots of color on their fins.

It definitely has a Molly shape to it, but it’s hard to see the details. OP, hatch some baby brine, all your fish will be happy.

 

[Seymo44]

It definitely has a Molly shape to it, but it’s hard to see the details. OP, hatch some baby brine, all your fish will be happy.

Yea the shape of the body right at the tail is what made me think molly. It’s hard to judge from the pics though, and I could be entirely wrong.