What is this really tiny creature on my glass?

[TehBrainz]

I was looking at the glass with my macro lens and stumbled across this small creature.

I've attached an image with a flatworm (I know I know ) to give size reference and a video to show movement. I'm lucky to have even seen it, it's so small

Video Link:

 

[Jacaine]

Looks like a baby crab to me.

 

[ISpeakForTheSeas]

I don’t know for sure, but it honestly looks like a super tiny crab to me.

 

[TehBrainz]

I don’t know for sure, but it honestly looks like a super tiny crab to me.

That's what I saw too and was kind of in shock with how small it was

 

[TehBrainz]

Where in the heck would it have come from? Maybe a baby emerald crab? That's the only one, besides hermits, in my tank

 

[ISpeakForTheSeas]

The emerald is probably a pretty safe bet, but how old is your tank? Did you use Live rock/sand, or have you have added any corals/macros recently? These are all possible entry points.

Unfortunately, the baby there is probably going to die (baby crabs have difficult diets to maintain), but if it lives I’d be excited to see what it turns into.

 

[TehBrainz]

The emerald is probably a pretty safe bet, but how old is your tank? Did you use Live rock/sand, or have you have added any corals/macros recently? These are all possible entry points.

Unfortunately, the baby there is probably going to die (baby crabs have difficult diets to maintain), but if it lives I’d be excited to see what it turns into.

This tank is almost a year old and was seeded with rock from my 3ish year old 75gallon. New sand. Last round of corals added maybe 3 months ago.

I tried looking for it again about 30 mins ago (picture was taken about 3 hrs ago) and couldn't find it. I'll assume it won't make it until I see a smaller emerald (or other crab) than my current one around the tank lol

 

[WVNed]

There are usually several steps in a crabs life before it looks like a crab so the one you saw was not born in your tank. They start life as plankton.