I purchased a yellow sea cucumber, Colochirus robustus, from my LFS yesterday. As my post history shows, I panicked when I first added him as their salinity was lower than expected - it was two points lower than my DT. I dripped him for about 90 minutes and then added him as the salinities matched. He quickly moved and found a spot on my glass and extended the tentacles to feed. He accepted food later last night. When I woke up he had his tentacles out but when I just went to feed him he had closed tentacles. Should I be concerned?