To keep your anemone alive, it will need much more lighting. Think of them like a flower that needs to be in direct sunlight.
Please understand, though it sounds like everyone is raining on your parade at this point, we don't want to see things turn out poorly for you or your new anemone friend.
Anemone need intense lighting to survive. It is normally suggested that they get a 6 bulb T5HO, MH
, or 2-3 watt per diode LED
panel. Though if this is a small tank, as we haven't had that part mentioned a 4 bulb T5HO unit could work as well.
Lighting aside, keeping your water parameters pristine and stable will assist you in keeping your anemone. When tanks are young, the parameters can fluctuate at times. To combat this, I would test my water frequently to ensure everything in the water column is pristine for your anemone...or if not you are able to do a quick water change to get it back to that point.