Some information about these zoanthids. Years ago, I got a few polyps from another RC member via a Thermos Trade, and these grew very slowly.
Several times I tried to share these with other local reefers, but every time they came back with reports of failure. They've grown steadily and adapted well to my reef. In the past few months, I've shared these with about 20 DFWMAS members. I followed up with those people, and had several post success and some growth. One person's melted away.
My reef is run with LR, DSB, refugium, MH lighting, Tunze & VorTech pumps, a large protein skimmer and Calcium Reactor.
I feed the tank daily with my own home-made fish food, and my mixed reef requires that I run fresh carbon actively. I change it out weekly.
I have many colonies of zoanthids throughout the tank. Some are near SPS, others near leathers, still others on the sand and rockwork. I have tiny polyps, medium sized polyps and very large zoanthid polyps.
I don't feel that they have any special needs nor specific requirements such as target feeding, but I do notice when salinity gets too high or too low, they can close up. So when zoas seem to be unhappy, I usually think about checking the salinity. (Salinity at 1.028sg or higher tends to close them up quickly)
I have observed and photographed a Tiger Cowrie chowing down on two patches of zoanthids (small polyped as well as the larger kind). I lent him to a local hobbyist to help him as his tank is overrun with zoas. Imagine that - too many zoanthids.
Water changes tend to be 55g at least monthly, but lately I'm changing the water more frequently and everything including my zoanthids seem to be happier.