I have a small flytrap and it is producing new leaves, but at the same time, leaves are turning black and dying. I have it is a sunny window, fairly warm, but I have been giving it tap water, which I see is a no-no. How big should this thing grow? Is it a good idea to transplant it. My new leaf groth has no pink color, only green. What can a novice do to improve growing conditions for this little guy?