Detritus?

I have a shrimp only tank with many little newborns so i don't really want to try and move them, or treat the tank if these are harmless. But these worms are multiplying and getting a little bigger than they used to be. I just want to make sure and confirm that these are the kind that are no big deal. There was quite a few behind the filter so i took a picture there.

Planaria or detritus worms.

Do a 75% water change and gravel clean the tank every day for a week and they will go back into the substrate where they normally live.

Usually a sign of overfeeding....

If i were to do even close to a 75% water change i would be doing a 100% and moving those shrimp to a new tank . Doing it daily isn't an option. The question i have is, are they the type that is harmless, can i leave it be for the time being?

I can't tell what species/ type they are due to the picture. But planaria and detritus worms are normally harmless. They usually live in the gravel and only come out if the gravel is really dirty, or there is a water quality issue.

Even one decent sized water change and complete gravel clean would probably be enough to get them to go back into the gravel.

Planaria worm always has the distinct triangle shaped head and there are slight differences in behavior of the "swimming"
Here is a nice article