Deficiencies of Aquatic Plants

Aquatic plants are plants that must grow in water or fully saturated soil. The plants have thin stems, which allow for easy water transport. The structure of aquatic plants is less rigid that of other plants because the water pressure in their environment supports them. Aquatic plants survive through carbon dioxide and photosynthesis. Without light, the plants cannot produce food. Aquatic plants can often suffer from deficiencies.

  1. Carbon Dioxide

    • A carbon dioxide deficiency is one of the most common problems with aquatic plants. This can happen even in well-cared-for environments. Too much aeration can cause a lack of carbon dioxide. The plants will be much smaller than normal and will grow very slowly. There will be calcium deposits on the leaves, and the pH in the water will be above 7.5.

    Manganese

    • A manganese deficiency will affect the new leaves of an aquatic plant. The tissue between the veins will become yellow, while the veins remain green. This is due to unbalanced iron in the water. An application of a balanced fertilizer will help restore the manganese levels in the water.

    Iron

    • An iron deficiency will cause the leaves to become yellow and brittle. The symptoms occur first in the new leaves of the plant. The leaves will eventually fall off or rot away. This is usually due to over-fertilization of phosphates in the water. The pH will usually be over 7.0. The best treatment is by applying a good iron-rich fertilizer.

    Magnesium

    • Plants with a magnesium deficiency will have yellow spots. They may also appear to be red due to the red pigment. Left untreated, the leaves will fall off and the plants will die. This can be treated with an application of aquatic plant food. You should follow the directions on the bottle according to the size of your aquarium. Aquatic plant food can be found at any pet food store that sells fish.

    Potassium

    • A potassium deficiency will result in the yellowing of the young leaves of an aquatic plant. Older leaves will begin to wither around the edges and eventually fall off. The carbon in your filter may cause the potassium levels in the water to be lowered. An application of aquatic plant food will help restore the potassium levels. Follow the directions on the bottle of plant food.