I have just started up yet another aquarium, a 10 gallon with live plants. Over the summer, I had great success with a 5.5 gallon tank using soil capped with gravel. I decided to use Caribsea Eco-Complete substrate this time around. In my 5.5, I didn't need to add any ferts because the soil provided all the nutrients my plants could possibly need. Eco-complete apparently contains nutrients such as iron, magnesium, and potassium, but I'm wondering if additional ferts are necessary. I'm not growing anything demanding, just standard fare for a low tech, low-to-medium lighting setup.