Expect yours to look like All Delights except bigger. His is the micro balanophyllia and I have some too. They are small...........a dendro is like waaaaaaaay bigger than that.
Feed it a few times a day and give it foods like mysis shrimp, flakes, pellets, squid, etc. Don't feed it too much or the dendro will throw up the food.
They are not hard to keep, I would just worry about water quality, thats the biggest issue with them. Also they open up all day so its easy to feed them while their relative the sun coral you have to kind of coax it to come out during the day.