Pic 1 (fca85683....) looks like a banded nem (Isarachnanthus nocturnus), they do not always live in the sand.
Other nem looks to be an Aiptasia diaphana or an Aiptasia pulchella. Possibly a type of exaiptasia also. The first being invasive and the second, not so much. The "possible" one it all depends on the type.The first 2 are being recorded in Gulf waters as of late and have been logged numerous times on some gulf rock collected. There is also the possibilty it could be a curlyque nem, as when little, they do not get as "curly". Hard to tell from the pic though. I am stil leaning towards one of the first 2 stated for this one.
With any of these, as the are NPS, they do not need light. But they can still be removed very easily.
You will want to remove the Aip one with a small nem cannon. Link below, just down size it to a 3/8" pex pipe or a slurpie straw in a really small sponge. I say to not nuke them, as both of those nems can self fertilize and that can lead to an outbreak. Using a nem cannon, even though they are NPS still works, as they will not want to sit in stagnet water with no flow. They will move up the "cannon" and then can be peeled off outside of the tank and disposed of. Kalk paste , lemon juice or vinegar can work, but I would try a small nem cannon first.
For the one that looks like a banded nem, I would just watch it to see if it reaches way up and out of the rock after lights out. If it does, it is a tube type nem for sure, if not, it could be "cousin" of the warty nem. They do not reproduce like mad, but will need to be fed to live. There are currently 9 types of these nems with no classification yet. Although that is being worked on.
End of day, you got some awesome stuff and one or 2 may need to go.
Here is the link to the nem cannon. Again, just down size it. 1/3 of the diameter of the nem usually works best, as they get smaller when they retract.
Due to seeing numerous post recently about how to remove anemones and shrooms without hurting them or destroying rock work. I felt like this was in order. First off, a little back story. Years ago, when I lived in Florida and collected aquatic life on a regular basis, we always had issues with...
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