Help identifying hitch hikers

I got some new live rock a few days ago and have noticed some interesting hitch hikers that I haven't seen before. Just wondering if any of them may be harmful and if anyone can help me identify them. I've had my 29 gallon tank running for just over a month. I have pictures.

The really long white things are spaghetti worms. I also see an aptaisa anemone, pineapple sponges, and even a leg of a brittle star. The only thing I would really be concerned about is the aptaisa nems. Those can take over your tank pretty quickly if not handled correctly. A peppermint shrimp loves to eat those things but its about a 50/50 shot. The pineapple sponges are usually a sign of poor water quality but nothing to be concerned with. You can just be sure to keep up on water changes and get nitrates down and they'll usually disappear from what I've been told. The brittle star is a good member of your cuc also. I'm no seasoned vet by any means so i would just do a quick Google search on the above mentioned hitchhikers and you'll find out! Good luck and happy reefing!

My water quality is good. I did a water change 2 weeks ago and my nitrates are almost 0. I did get that rock at a pet store though so the water it came from might have been poor quality. What about coral banded shrimp, will those eat the aptaisa?

No coral banded shrimp won't touch them. How long have you had the rock in your system?

3 days

Well you can try adding a peppermint shrimp to battle the nems but from what I hear if you already have a cbs they can get territorial and could kill it. Which wouldn't be so bad seeing as they're not expensive at all so it's worth a shot and probably the easiest way to start. I think petco sells them for 6 or 7 bucks. Also you could try boiling water injections at the base of them or Aptaisa X works well. As for the sponges I wouldn't worry about them if your water parameters are in check they should die off soon just keep an eye on them. What ever you do, don't try removing the nems or sponges by hand bc you could squish them and they'll release spores and spread like wildfire. If you don't mind me asking, what store did you purchase the rock from?

You could also take some super glue and hit the nems with that. There have been some guys on another forum who had luck just gluing their butts back into the hole they came from lol

I got it at petco. It's really the only place where I live that has saltwater stuff and they had them 50% off

Personally I will never buy live rock from petco again. My first tank just about crashed because of their "premium live Fiji rock". It's not cured and most of the time it looks like a solid piece of base rock that is non porous and covered in who knows what! Not trying to come off as insensitive but if you got it at the store here in Longview while they had their %50 off sale I would chunk it in the backyard where it belongs. They're trying to get rid of it for a reason! Nobody wants it lol

Yeah, where would you get live rock from? The only other place I know that has any is wet pets and theirs usually looks worse than petco. I've been pretty picky about the rocks I get to make sure they're porous and haven't had problems in the past. Also now that I'm home and can look at things a little closer I see the aptaisa it probably has around 15 tentacles and is pretty small. There's also the other one that has about 8 and can retract when the snails get near it. The second one doesn't really look like the pictures of aptaisa that I've seen. I also think that what might might look like the pineapple sponge in the picture might not be that. I do have some snail eggs on the rocks and some hard white tubes that are hollow that are out of focus in the picture so they look fuzzy.