No, if it is struggling, don't fertilize it.
What kind of light is it in? I had one that I kept in my bathroom for several years. It had zero direct light, just light coming in through the frosted bathroom window. It sat in a bowl of water and I never did anything to it but add more water. It flourished. When it got too huge to stay in the bathroom, I tried to take it outside, but it promptly died when the sun touched it, even in a pretty protected spot.