New updates!
Tonight, I found something caught in between two of the LR, i thought it was the so-called "kraken"

to be honest I was a little excited, so anxious to catch it, and as soon as the net went in the surface of the water, it started to move trying to hide , then stopped. I then took out the fish net and used my hand to remove the rock, then it ran away, I used a flashlight to search the area and finally came to realize that it was just a crab...quite a bit of size...bigger than regular small hermits....duno what type , but shell is all the same color as the rocks... with algeas on the back of it...didn't get a chance to see the pincer...but it's got strong looking limbs, so I assume it's pincer is probably big as well, would it do any harm to my tank? like kill inverts or mess around with corals or kill fish? I think it's already messed up one of my small LR settings...was straight stick into the sand bed, now it's fallen on the side=.= (the shell from my first post, probably belongs to him....so...imaging 1.5~2 times the size of that for just the shell...)
Also, along with the false limpet I caught last time, I also found something else...also look like a slug, but i only saw one third of the body of it, so I can't tell what it is, and I can't really catch it cause it's in the middle of my whole settings....gonna wait until it comes out.
P.S. Does clamp move? like not the ones you buy and keep in coral reef, but the ones you use to make clam chowder...? Cause I think I have one in the tank except I cannot catch it cause it's been moving around and hiding in holes of the LRs....