[ID] I have no idea what this thing is, can you help me ID these things?

[meanduck124]

This new 5g Pom Pom crab tank is in cycling, but today when I look over and I see these little bugs, or snail, or something in there. At first, I thought they were some kind of snails but I notice they have 2 antenna on their heads and they crawl like bugs, but I couldnt find anything about these online. Can you help me ID if these are harmless or harmful to the Pom Pom crab please.
Edit: Sorry for the low quality but this is the best I can film them.

[mcarroll]

You may have to get a better pic somehow....they look like detritus to me.  😬

[meanduck124]

1 hour ago, mcarroll said:

You may have to get a better pic somehow....they look like detritus to me.  😬

This is the closest I can film them, they are really small. I thought they were juvenile amphipod but they are much slower.

 

[mcarroll]

Wow, that's pretty cool looking!  (Is that on the tank wall?)

 

Not much but a guess: Baby horseshoe crab?   I think those are bigger tho...

 

Maybe Isopod, but not really seeing the "telltale" eyespots...

http://www.wetwebmedia.com/isopodid.htm

 

Also take a read-through here...lots of back and forth (as there should be): 

 

[meanduck124]

2 hours ago, mcarroll said:

Wow, that's pretty cool looking!  (Is that on the tank wall?)

 

Not much but a guess: Baby horseshoe crab?   I think those are bigger tho...

 

Maybe Isopod, but not really seeing the "telltale" eyespots...

http://www.wetwebmedia.com/isopodid.htm

 

Also take a read-through here...lots of back and forth (as there should be): 

 

Someone said that it might be daphnia but I dont see the resemblance. They are incapable of crawling on the tank wall, I only see them on the rock. I dont think it either isopod or cirolanids. 

[mcarroll]

Some of the pics in that thread I linked looked quite a bit like your specimen....but they also aren't the most detailed photos.

 

I've never heard of daphnia showing up in a reef tank, but I guess it's possible.  After a quick googling, I don't really see anything "daphnia" that resembles what you have....the motion in particular.  

 

Daphnia all seem to have legs prominently "up front" whereas your critter has legs spaced more or less around the whole body.  (Right?)

 

(Love a good reef mystery!)

[meanduck124]

15 hours ago, mcarroll said:

Some of the pics in that thread I linked looked quite a bit like your specimen....but they also aren't the most detailed photos.

 

I've never heard of daphnia showing up in a reef tank, but I guess it's possible.  After a quick googling, I don't really see anything "daphnia" that resembles what you have....the motion in particular.  

 

Daphnia all seem to have legs prominently "up front" whereas your critter has legs spaced more or less around the whole body.  (Right?)

 

(Love a good reef mystery!)

They are hiding as soon as I got a microscope, these things can sense me coming for them.