what is this growing on my rock
 

i have something growing on my live rock it is white and slimy to the touch and it almost looks like bubbly spit on my rock or something what is it and is it bad ?

Scruba dub dub
 

It may just be a sponge....can you get a picture?
If it looks like something similar to what spit bugs leave on grass...I'd think a sponge (though there are a few different looks and forms, but the one I have in my tank looks like that.).

yup
 

ya it looks just like the spit bigs leave on grass it is growing on the underside or pretty much every rock i have i did not notice it untill i had to catch my wrass and pulled all the rock out is it anything to worry about

Sponges are actually good for a tank I believe.