what the heck is this new horror?

[Theulli]

It doesn’t look alive but how did it suddenly climb up the glass?

 

[Theulli]

Never mind it’s moving, very face hugger esque

 

[ScottR]

Spaghetti worm. Harmless CUC

 

[Theulli]

Yuk! Haha I don’t know how I have had this tank for 12 months and new critters are still appearing. Oh well if it is CuC I can live with it, even if it is a bit Lovecraftean

 

[Theulli]

So reading up my next question is - why is it hanging out on the glass? Seems like they are substrate dwellers

 

[ScottR]

They’re worms so they’ll move around. They sometimes crawl up the glass but it’ll probably make its way back down to the sand.

 

[Theulli]

Cool just wanted to make sure seeing them suddenly wasn’t a water quality indicator

 

[ScottR]

Cool just wanted to make sure seeing them suddenly wasn’t a water quality indicator

I doubt it’s a water quality indicator because the sand bed is usually a very nasty place even in tanks with good water quality. I do see what looks like cyano (the reddish stuff) in your sand but I highly doubt it would bother the worms.