The leaves do not grow right out of the bulb like an Aponogeton. The bulb sprouts, grows into a stem that the leaves grow from. The roots form from the base of the stem not the bulb. The plant can be easily separated from the bulb and a new plant will usually form within a few weeks. Under proper conditions Tiger Lotus gets quite large, the leaves the size of your hand and a root system a couple feet or more. Feeding it NPK at the roots will make it go nuts very quickly. A pot will restrict its growth and feeding. The bulb may stop producing new plants if it is not fed properly, or if light is weak. Plants that are separate from the bulb may produce new bulbs if the plants reach maturity. If you keep them stunted that is not likely to happen. It is not a good idea to bury the bulb. You can let it sit on top of the gravel, or bury the bottom half. As long as the roots reach the gravel it will be fine.