For the beginning Aquatic Gardner recognizing plant deficiencies is probably the hardest thing to learn. Several different deficiencies will appear to look almost the same. Couple that with the fact that a new tank has rapidly changing conditions that make it difficult for a veteran aquatic gardener to properly diagnose. List below are the most commonly occurring plant deficiencies and how to recognize them.
Old Leaves turn yellowish or sometimes reddish. Small stunted plants with very large root systems; leaves smaller and lighter in color than normal; slow growth. Paleness will start at the tips of the lower leaves. Older leaves die off quickly in extreme deficiencies. If this deficiency continues, the foliage will continue to develop, but stems will be spindly, sappy and soft, flowering will be delayed, small fruit will grow and the plant will be more susceptible to disease. Lack of lush green color especially in older leaves.
Toxicity - soft, dark green leaves, long weak stems, poor root development and slow to maturation.
|Iron (Fe)||New||Leaves turn yellow and become brittle and glassy an disintegrate
Greenish nerves enclosing yellow leaf tissue First seen in fast growing
plants. Tips of new leaves will become either pale of yellow, and this
will spread inward. The leaf will likely turn blotchy from a lack of
green pigment, eventually turning brown and drying out.|
Toxicity - Deficiencies of other elements, brown spots on leaves.
|Potassium (K)||Old||Yellow areas, then withering of leaf edges and tips. In early
stages, yellowing and curling of older leaves. Newer leaves will begin
to droop. Older leaves then become blotchy and scorched. Flowers are
lackluster, and stems are soft. The plants will be more susceptible to
diseases. Pinpoint holes in leaves.|
Toxicity - saline conditions, marginal leaf burn, wilting. May cause calcium deficiency in soft water condtions with excess potassium.
|Magnesium||Old||Symptoms do not appear until the deficiency is well established.
The plant will be stunted. Leaf veins will stay green while the
remainder of the leaf turns yellow. Brow spots will appear and the
plant will dry out. Flowers will be slow to develop, if at all. Flowers
that do grow will be lackluster.|
Toxicity - edge curl on leaves, small stems, signs of potassium deficiency.
|Phosphorus||Old||Premature leaf fall-off Similar to nitrogen deficiency. Stunted
plants with dark, dull, and sometimes discolored leaves, unusually hard
stems, poor root system and very little branching. Attacks lower, more
mature leaves first. Occurs especially when nitrogen level is low.|
Toxicity - small curled new leaves, early maturation, large root systems.
|Calcium (Ca)||New||Damage and die off of growing points Yellowish leaf edges.
Underdeveloped roots are the first to be affected. Younger leaves will
be immobile and their edges will curl. Plants will be stunted and have
dark, crinkled leaves.|
Toxicity - iron and potassium lockup.