Different anemones have different lighting needs. These Inferno's cope under most lighting, and even poor lighting. I would check all the critical parameters, Alkalinity/Calcium/magnesium/Phosphate and Nitrate. I think your PH is to low needs to be up at 8 to 8.2.
I never feed my Inferno, but my nutrients are high, and I have a high fish stock, so feeding the fish normal food feeds the inferno's.
I do however feed my purple and red Heteractis Magnifica anemone's, which are rather large once a week with a 1cm cube Clean, skinless, non cooked Hake. Make sure the anemone does in fact eat the food you are feeding. You need to make sure of it.