They actually do look like some type of tube. I also have them on some rock in my tank right now as well. I don't want them taking over. Any idea what kind of worms?
I asked this question in one of my Facebook groups and we have come to the conclusion that these are hydroides elegans. In other words, my worst nightmare. They are on one of my base rocks so I can't remove the rock to clean them off. Thank you for trying to help!
They are not hydroids, hydroids don't make a hard tube or spike, they are soft bodied.
Serpulid feather duster worms (calcium carbonate tubes) - harmless filter-feeders.
That's kind of what I was thinking, but my eyes couldn't find any of the "feathers" lol! But they reminded me of the little feather dusters I've had in my tanks.
The picture that you are referencing is the coral skeleton that has been out of my tank for weeks so it has been dry. I just took a small brush and brushed some of the ones currently in my tank on the rock. They brushed away easily. I can't physically touch them as my tank is 36" deep so I can't reach the bottom without scuba gear...lol. While floating around in the current one got caught on a rock and it is moving like a noodle in the current so definitely not tubes. They are maybe a centimeter long.
Looking at the video, none of the tubes I was looking at in any of the pics are moving in flow (indicating they're pretty solid), but I do see the thing flowing in the video. Between that and your comment in the first post that they're hard white spikes, I'm thinking we're looking at different stuff here.
Definitely not vermetid snail mucous net. Let me see if I can capture some with my long net tomorrow and get it into a bowl of saltwater with white light. I may try to dive in and actually feel them with my fingers to determine if they are hard in the water. I'll update tomorrow. Thank you for trying to help. I've had saltwater tanks for 5+ years and I am stumped. Haven't added anything to this tank for at least a year.
