Saltwater aquarium problem.

[FesteringGob]

I was wondering if anyone could tell me if these are bad or are good for the tank. I have a 20 gallon tank with a rosebud anemone, yellow wrasse, tomato clown, 2 damsels, foxface, crabs, and a horseshoe crab. I have noticed that I have a strange growth coming out of the sand. I thought it was algea but it is not. It is a worm like thing. I have a couple of pictures. Also my live rock has a thick white and pink "mold" growing on it. Is it safe as well? Do I have something wrong with my tank. Sorry, I am still learning everything about saltwater.

Pic 1
Pic 2
Pic 3

I know they are huge, but I wanted to be able to show the detail of the things. I pulled one out of the sand last night. It looks like a worm and all the long things are growing off it it. I have about 6 in the tank and have no idea what they are or where they came from.


Thanks.

 

[Fluff]

They are spaghetti worms (sand mason worms) They are good hitchhikers. They consume detrius.

 

[FesteringGob]

Thank you. Should i be worried that there are a good many or should I just leave them be? I was just freaked out when the started to move. I did not realize they were alive. I thought it was some kind of algea or something.

 

[melosu58]

Don`t worry be happy. They are good they will take care of the fish waste that falls to the bottom as fluff said. But I do worry about the horseshoe crab in a 20 gallon tank. Too small. Hopefully you`ll upgrade to a 210 later

 

[FesteringGob]

Not sure when, but I am working on a 120 gallon. Don't know when I could cough up the dough for a 210. Would be nice though

 

[Fluff]

The problem with keeping horseshoe crabs in an aquarium is they will clean your sand bed of fauna then starve to death. Good luck.