They probably will not unless they are wild-caught and picassos are not wild since they are specialties by captive breeding. IME if the anemone is 8" or bigger you can just place it in a nice, deep hole in the rocks and it will stay but only if the hole blocks the foot from any water movement and the hole has a bottom... so I'd say about a 1.5" deep by 1.5" across would do it as long as the anemone fits snuggly in there. RBTA will move around the tank if the water quality is bad, the lighting is too much/too little, or it's not getting enough food. How big is your tank? How many corals do you have in it? Can you post a picture of your tank? Also, it doesn't have to be an RBTA. An RBTA is the same as a BTA but it just has a different color pigment. I'm not sure why there is such a huge price difference, but I'm finding that within the last year or so that BTA are harder to find than RBTA. If you don't live near a store that has anemone, I know a great website that sells cheap, healthy, beautiful BTA!