The oxygenating plants are a must for any water garden. Oxygenating plants compete with algae in the pond for nutrients in the water. This helps to keep the pond water clearer. Oxygenating plants are submerged plants and should either be planted in small pots filled with gravel or weighted with lead weights and sunk to the bottom of the pond. Because you want the oxygenating plants to consume nutrients in the water garden you should not fertilize them. A good rule of thumb for how many oxygenating plants you should have is one bunch per three to five square feet of pond surface area. Using that ratio a 6 foot by 8 foot water garden should need 10 to 15 bunches of oxygenating plants.
