1inch aquatic soil enough for plants?
Hi all, new to planted tanks and wanting to attempt a Walstad tank in particular. I had my tank semi set up at the store, and was given 1inch of black aquatic soil (the type that forms gravel-like balls) that has NPK and bacteria in it to cover the base of my ~20L tank. When I started to plant my plants into the substrate at home I found it really difficult to get it to hold in the substrate.
Should I increase the substrate layer to more than 1 inch? In particular for the Walstad tank, is aquatic soil comparable to using the dirted tank method with regular soil, or should I redo the soil with regular soil underneath the aquatic soil?