Worm and tube identification

[mherb24]

I’m about to perform a water change and noticed little tubes coming out of the sand, all over, not just in one area.

Then I see some sort of worm, I’m good with it if it’s not a pest. I know some things are good additions, but is this one?

attached a picture of both:

Are are my parameters:

ph - 8.2
amonia - 0
nitrite - 0
nitrate - 10
calcium - 380
kh - 11
phos - .25
magnesium - 1350
salinity - 1.024

 

[Isopod80]

Looks like spaghetti worms. Harmless detritivores.

 

[afrokobe]

the top picture almost looks like some of macroalgae almost since its green in color. I think the bottom probably is just a bristle worm.

Here's a spaghetti worm in my tank, if it looks similar to yours