Id please?

[fishdude123]

maybe some isopod?
started noticing these pop up everywhere in my tank.

 

[fishdude123]

Picture of them on top of sandbed,

 

[blueblue]

Please identify.

 

[fishdude123]

Please identify.

Spaghetti worm?

 

[blueblue]

Does someone know what this is

 

[Mebbid]

Looks like Criolanid Isopods

https://tbsaltwater.com/blogs/reef-not-safe/isopod-cirolanid

 

[Mebbid]

Does someone know what this is

Spaghetti worm, generally harmless reef tank inhabitant.

 

[fishdude123]

Looking at pics online this may look more like sphaeromatid isopods?

 

[Mebbid]

Looking at pics online this may look more like sphaeromatid isopods?

Over 4000 species of marine isopods out there. Had to say which one specifically. Definitely an isopod of some sort.

 

[ISpeakForTheSeas]

maybe some isopod?
started noticing these pop up everywhere in my tank.

Definitely isopods - for telling if they're good or bad:

OP, these are probably harmless, but you can verify that if they roll into a ball (conglobate) when disturbed (like a rolypoly or pill bug; if they do this, they're keepers) and/or by looking at their back half and tail on the topside and underside of the critters (vaulted/domed underside of the tail end is good even if it can't roll in a ball; flat underside is bad and can't roll in a ball).

For the more technical explanation:

Yeah, learning to ID these can be a little tricky - I'll link the taxonomic key and stuff to help you figure it out if you want below.

Anyway, generally speaking, there are two superfamilies of marine isopods that can look superficially like this: Sphaeromatoidea (good guys that won't hurt you or your fish) and Cymothooidea (bad guys for our purposes). You can tell them apart by looking at the telson (technically a pleotelson) on the critter; domed (rounded) telson = good, flat/flattened telson = bad.

I can't tell for sure from your pics, but I would guess yours are Sphaeromatid Isopods (A.K.A. Seapills); you may have an easier timer telling in person than I can from pics though (side shot pics of the telson top and bottom would be useful for me).

The key (they do a simplified key for North American isopods, then a technical key for global isopods - I prefer the technical key):
https://www.americanisopodsmyriapods.com/taxonomic-guide-to-isopods-of-north-america/isopodaSome resources to help figure out the key (the third link shows some examples of isopods with larger pleotelsons than the first link; the isopods you've got have a larger pleotelson, so looking at both links should give you a pretty good idea of what the pleotelson is even with some variation in size/shape):

And here are some pages with diagrams to figure out the morphology (I like the first and second ones for figuring out the general pieces/makeup of the bodies, but the third is very technically detailed):
Crustacea Glossary https://isopod.site/isopod-anatomy-and-biology/ Untitled 1