mystery creature

Hey I just took a picture of these things growing in my tank. They started out as two small patches, around 1 centimeter in diameter, but now have grown almost 2 inches wide. It is definitely not algae. It is some kind of animal i guess. You can see the large openings like the mouth of an...

Can anyone tell me if this snail is good or bad? I spotted it this morning crawling around my sand bed. It's in a cup of water atm so speedy ID is hoped for lol. I'm not sure if it's a good kind to put back in or a bad kill it kind. o.o

I recently asked people what a mystery creature was....everyone was very helpful in naming it a limpit Since then it has fallen to the CC but the "foot" stayed on the glass......but the shell is still moving locations and not because of current What's going on? By the way... this...

I found these two orange what look to be polyps that are slowly growing and when i look at them really close they kinda look like single sun polyps idk.. maybe their some kind of hitchhiker..

Tonight I came home and found this creature on the back glass of my tank. Does anyone have any ideas as to what it is? Should I remove it, etc.

So this morning we found this creature on the front glass of the tank. No clue as to what it is or how it got there. It is very small perhaps 4cm in size. Can someone identify this mystery creature? Thanks Dianne

I found these itty-bitty anenome type things on a rock in my tank. The photo site where I finally found the picture calls it a cup coral, but I can't see a skeleton under them. They come out at night and are smaller than a dime. I've tried wall papering them in with epoxy, but they slink back...