Hi! I have many bubble tips and rock flowers so let me help
Bubbletips will walk until they find these 3 things
1. Optimal light
2. Optimal flow
3. A deep crevice/hole for the foot
If this is a biocube with stock lights, that's not going to keep the nem happy and it will continue to move. I suggest a minimum of an AI Prime (non-HD is fine).
Flow is usually okay in any tank. If you have some kind of euphyllia doing well then theres enough flow for a nem dont worry about this one too much
If your rocks are very smooth, boulder type, or artificial then chances are that you will need to place some holey live rock in there to provide a secure place for the anemone to attach its foot. Pukani is my favorite but rubble, wet live rock, dry rock, just any kind of rock with deep crevices will be perfect. If you can see it's foot, chances are that the nem isn't really happy and will continue to move. When my nems settle permanently I cannot see the exact point of attachment. When they shrivel up at night to sleep, they almost disappear because the foot is so deep in the rock. This is true for rainbows, CSB, Sunset Strip, Black Widow, etc BTA and probably all of them since the names are just color morphs and they are all the same species.
I do recommend feeding at least 1x per week but this is not necessary and many people dont do it. Personally, I feed mine every day or every other day with LRS nano reef frenzy or mysis shrimp and it produces large bubbles, vibrant colors, and extreme speckling.
Rock flowers are unlike bubble tips in that they do not split to reproduce. They will only reproduce through timed spawning events which according to the Rock Flower thread by Ron Reefman, may coincide with the equinoxes. These also need the Big 3 of the BTA but do not need as much light. Pretty much any light will keep a RFA happy. I recommend feeding them at least 2x per week (I use just one mysis shrimp per nem) so they keep their colors. I found that mine began to wither away when I did not provide this feeding and now they are all happy and healthy.
Hope this helps!