sweeper tentacles?

i have a couple different types of corals and have done research on each of them. they are supposed to send out long tentacles, i think their called sweeper tentacles. for example, i bought a galaxia frag at the store, when i saw it, it had a bunch of extra long tentacles the extended roughly 6 inch from normal extention. my question is; is it a sign of good health when they send those tentacles out or is it a distress signal. and on some of my other corals, their feeding tentacles hardly ever come out on ones such as lobophylia, favia and acans. does the lack of these tentacles reflect bad conditions in my tank?

 

I'm not so sure if it's even known why sometimes a LPS coral will extend it's tentacles and sometimes it won't; However, a receding polyp would be the first sign that something is wrong with water conditions.

 

Sweeper tenticles are typically used to keep other coral from invading into the space where your galaxia is growing.

As for extension from your other LPS, I would suggest you look at night to see if they are extending. that is when they typically feed. I rarely see my favia/ acans extend during my the "day", but at night they are completely different