First off, Heteractis magnifica are not for beginner aquarists (or anemone owner) and almost always require antibiotic treatment which is a big undertaking and not to be taken lightly. Secondly a 34g tank is absolutely not recommended for one of these touchy anemones, not only do they get too big but in a tank that small you're asking for trouble unless you have years of experience with these anemones. I can count on one hand the people I think could pull this off long-term, chemistry in those tanks is tough and what's even worse is the fact that a puréed anemone is much more likely if you don't know how to read them properly.
To answer your question, I don't think that's sufficient lighting, magnifcas love to be blasted with light.