Aquatic holeless pots are prefect for lilies, Lotus, and aggressive marginal plants. They will contain the roots and enable you to fertilize for maximum blooms. Plant in clay-type soil and top off with pea gravel to hold soil in containers. If you have large Koi, top off with larger river rock gravel.
Baskets make for easy planting, place plant in pot and add pea gravel. No soil!
Lilies and Lotus are heavy feeders and you will be rewarded with beautiful and plentiful blooms by fertilizing. Most marginals do not need fertilizer, they take their energy from the water. You may choose to fertilize flowering marginals such as Iris (early Spring only) and water cannas to encourage blooms.