I have literally dozens of houseplants. As mrV said, being a variegated variety of dracaena, your plant will require slightly more light than some other dracaenas do. If the leaves start to go mono-colour, it needs slightly more light. However, midday direct sunlight will burn the leaves; placement in an eastern facing window should be ideal. When you re-pot it, go up only one pot size; dracaenas like to have somewhat crowded rootballs. Spring is really a much better time to transplant your plants, but that one does look like it would benefit greatly from some fresh soil and a larger pot. When you water it, let it dry out slightly between waterings, but never so it's thoroughly dried out. If you keep it constantly waterlogged, the crown will eventually rot, hence why it will not stay in aquaria forever. By all means, do water any plants you have with water you remove from your tanks during water changes; it is the only fertilizer my plants get now, and they are all healthier and blooming more than they ever did with chemical additives.