My tank is still cycling and I've noticed that some of my plants are starting to die. Their leaves are turning yellow. I did add some iron supplements to the gravel but according to the directions its not time yet for another dose of iron. I'm not sure if it is because of a lack of iron, light. or something else. I know with an established
nitrogen cycle nitrates are produced which are then used by plants. Could they be dying because of too few nitrates? I will admit that I only have a 15 watt light over my tank (20 gal). I thought I could get away with have an argentine sword plant in my tank but maybe it's not getting enough light? My microsword isn't looking too good either. If you think I should upgrade my lights do you have any suggestions about what kind of light I should get? and do I need to buy a glass hood or can I find a higher watt light that will fit into the top of my aquarium?