ID help -White Worms in sandbed

[CloudReefer]

I found these two worms under a piece of rock I was moving. They slithered their way back into the sand bed pretty quickly. Both are about 5cm long and relatively thick, maybe 4-5mm?

The rock they were under was from Florida (Tampa Bay Saltwater).

I think I might have seen sand grains inside the things. If that's the case I'm guessing they are living on microfauna in the sandbed.

I let them be as they have been in my tank for 9 months and haven't caused any apparent problems.

Never seen worms like this though. Only really concerned about my wrasses sleeping in the sand but haven't had a problem yet, knock on wood.

Can anyone help with an ID please?

Thanks!

 

[JGT]

Look like peanut worms. Harmless and good scavengers.