Don't feed anemones too often. Once a week is pretty much sufficient. Anything more & you'll be killing it with love.. This applies especially to newly introduced anemones. After they have replaced all their nematocyst cells that have been lost during shipping and have acclimated to their surroundings, you can feed them twice a week but not more than that. Anemones use up alot of energy to digest their meals. If they spend more energy digesting their meals than what they can gain during photosynthesis, it will not be a very good thing. Different types of anemones prefer different foods. For instance carpet anemones prefer bigger chunks of food like a whole market prawn while bubble-tip anemones in nature consume small zooplankton like rotifers, etc. Rarely are the stings of bubble-tip anemones strong enough in the wild to capture significantly large sized prey. Different anemones will prefer different substrates. Tube & carpet anemones like to burrow their foot into FINE substrate in the wild. Bubble tip anemones can be found naturally on reefs. It is best to duplicate their environment in which they are found in if not most anemones will not survive for long.
Do notE that most anemones are not treated in the best of conditions upon arrival. Most farms/LFS simply empty all anemones into a tub of water regardless of species. This is one of the main reasons why it's hard to get a healthy specimen. Mixing of different species of anemones in tubs even for the shortest of periods will trigger massive nematocyst warfare (due to glutathione released by anemones during stress, which serves as a signal for nematocysts to fire). The result is simply weakened anemones that are made available to the hobbyists.