i agree with the "they'll host anything" i have 2 percs in my 29 gallon, they chose to host the powerhead and i have Torch/Hammer/Frogspawn coral in their. They swim thru it once in a blue moon but still decide against hosting....I figured with 3 choices, and all 3 are BIG pieces they'd like 1 of them, but i was wrong
it is basically luck sadly to say, im planning on buying an anemone soon for them and HOPE they host that