What are these worms and how do I get rid of them?

[tractorjackson]

They showed up in my 3 gallon beta tank 8 months ago. It killed the beta. I took all decorations out and boiled them as well as flushed the tank with boiling hot water. I have a 40 $ 29 gallon tank. I put the lava rock that was in the tank into my 40 gallon last week and switched out some decorations between the 2 large tanks....now both have these
How can I get rod of them and not hurt my fish?

 

[coralbandit]

See if planaria match up? They are usually from overfeeding but can be killed with a simple med.

 

[tractorjackson]

See if planaria match up? They are usually from overfeeding but can be killed with a simple med.

Seems weird that it spread from one to the other. I’ll look up planaria. Thanks