First what kind oa coral is this and isn't it cool to see the clown hosting in this. I have only had the coral for about 2 months. But I have had a LTA for about 5 months and she never took to it but oh well this is much cooler
Nice pic. The coral looks to be some sort of Alveopora sp. and IIRC they have a poor track record long-term in aquaria as their care requirements are similar to Goiniopora sp.
A.frenatus only naturally hosts in BTAs, so sometimes it's hard to get them to host in other anemones. Too often, they choose a coral instead, as you've found out