Word of warning, when RBTAs are on the pink side it is an indication of bleaching, however mild. A truly healthy RBTA is red. If you have an RBTA which is pink I would suggest reduced light and increased feeding until it returns to a normal red coloration.
The bubble-tipping of Entacmea seems to be increased by hosting a clownfish. But being a flow-centric guy I blame it all on flow. You will rarely see a BTA without bubbles if it is in good, strong flow.
i just fed mine a little silverside it just took the whole thing in. and its a huge rose bubble tip really nice color will post pics when my original pc will get fixed...