Btas are probably the only anemones that can handle inferior water chemistry. However, I wouldn't just throw it in based upon that. I would suggest doing a big water change to get nitrates down as much as possible, then introduce the anemone. That way when nitrates build up the nem can adjust slowly as the nitrates rise. Building Tolerance so to speak. I would definitely keep a eye out though because with nitrates over 100, if the anemone dies, it will push parameters to a definate tipping point for the rest of the inhabitants. My 2 cents.