Diagnosing Nutrition Deficiency
So I've had my 90gal planted tank for a few years, medium planted with moderate light and low injection of CO2. I have Eco Complete substrate and use root tabs. Everything has been running fine and I've been very happy with my tank. Recently I've noticed that my anabas nana is starting to yellow on the older leaves and when I uprooted it to split it the stem. The stem was very weak and snapped in my hand where as before I had to saw it in half. The Amaranth redroot leaves are thinning "becoming transparent". I believe that I now need to does fertz. I've ordered dry fertilizer and am going to start dosing but I am having trouble finding out what deficiency is causing what symptom?
Question is how will
Affect my plants?
For example if leaves remain yellow I should increase dosage of XXXX?