Question

Question
I java a 100 Hal. Saltwater tank.  In the substrate there are clear tentacle
Like ars waving around protruding from the substrate.  What are they?

Answer
antonia,

these could be some sort of invasive anemone. either aptasia or majano. i would suggest getting something such as aptasia-x to rid the tank of this nuisance or get an animal in your tank that will consume them. many types of ornamental shrimp and crabs will i believe. as well as several species of butterfly fish.