Ozadars - Your tank is only 3 weeks old? Did it cycle? Without getting into pulling them out of the ocean yourself, when you found them, how were they situated? Were they in shallow water? Exposed to the sun? If so, even a cold water anemone will need more than 2-18w bulbs for long term survivability.
Meaty foods help, but are not enough. I am speaking from experience with inadequate lights for anemone's.
myescape0- I don't think your clown is smothering your anemone's to death. That's what they do. Are the anemone's much smaller than the clown?
What are your water parameters? How much current is in the tank?
Anemone's will shrivel regularly. Don't read into it. They have one opening, and expel waste through the same opening they eat with. When they do, they expel all the water from them, and then suck in new water.