Hygrophila corymbosa 'Stricta' is a form with narrow leaves.3 Its species, the giant hygrophila, comes from South-East Asia and is cultivated in several genetically stable forms.1 It is said to come from Thailand and is regarded as extremely hardy and suitable for beginners.2 It is also traded as Nomaphila stricta or Hygrophila 'Angustifolia Rubra'.3
Submersed, the leaves are light to medium green, sometimes almost ribbon-like and up to approx. 19 cm long; grown in air they are lanceolate with a red-brown tint.3 The stem plant grows fairly quickly, tolerates hard water and needs only medium light; with a potassium deficiency the older leaves of Hygrophila species quickly develop holes.3 In larger aquariums it is used in groups in the midground or background.3
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