I keep reading that you should transplant VFTs every year or two, does anyone know what the limiting factor is? I have heard soil acidity, nutrient leaching, etc. but a paper on www.bestcarnivorousplants.com mentioned that even among CPs that VFTs are particularly sensitive to nutrients in the soil so could the problem be nutrient accumulations that could be removed by top watering instead of using the tray system? Has anyone tried this? Did it delay the need to transplant? Curious am I, yes.