Worm or snail poop??

[SaltyShel]

Hey so I moved my snail (I think it’s a turbo) and hermit crab from my other tank into this one. I didn’t do an official QT, I just scrubbed the shells really well in a bowl of new + old tank water and then once really clean I dunked them separately in a new dish of RODI. I thought that would be good enough, since a LFS owner told me it would.

Now keep in mind, there was literally nothing in this tank, it was all brand new rock. Bare bottom. Everything brand new so there’s obvi no way I introduced anything prior to these inverts. I did also put my fish in here and he passed away the other night. Idk if he had something wrong with him or not.

now Im noticing these weird brown lines everywhere. One of them was wrapped up in the snail when I pulled it out with tweezers. Once out of water, it shriveled up basically. Someone please tell me what this is, how serious it is/isn’t, and how the hell I get rid of them!!! i just can’t believe I already have something in here. it blows my mind. I thought I cleaned them enough. Maybe it was the fish. Or is this brown thing snail poop? This is the only area I’ve seen them and the only place my snail sits.

 

[SaltyShel]

i also have these white things that were not here before. Idk what it is please if anyone Can ID and tell me what it is, how to get rid of it, if it’s serious, maybe even tell me how did I get it??