Pengertian Dasar NFT

Dr Allen Cooper dalam bukunya The ABC of NFT menyebutkan :

” Nutrient Film technique crop production (commonly know as NFT Cropping) is a method of growing in which the plant have their roots in a shallow stream of recirculating water, which are dissolved all the elements required. There is no solid rooting medium. A root mat develops which is partly in the shallow stream of recilculating water and partly above it. Thus , the stream is very shallow and the upper surface of the root mat which develops above the water, althought it is moist, is in the air. So arround the roots which are the air, there is a film of nutrient solution hence the name nutrient film technique It is extremly important to maintain the basic principle of a nutrient film because it confers an important advantage. In NFT crop there is a permanet abudance of both air and water at root provided the nutrient film principle is maintained The key requirements in archieving a nutrient-film situation are :

a. To ensure that the gradient down which the water flows is uniform and not subject to localised depressions, not even a depression of few millimeters

b. The inlet flow rate must no be rapid that a considerable depth of water flows down the gradient

c. The widht of the channels in which the roots are confined must be adequate to avoid any damming-up of the water by the root mat since, if in adequate, it is to be expexted that yield will be direcly proportional to the channel widht

d. The base of chanel must be flat and not curved, because trhere will be a considerable depth of liquid along the centre line of chanel with a curved base, merely because of the shape of base “

Kalau boleh kami terjemahkan dengan bahasa sederhana intinya, konsep dasar NFT adalah mengalirkan nutrisi hidroponik ke akar tanaman secara tipis (setipis film). Dengan aliran tipis ini tidak semua bagian akar terendam air, masih ada bagian akar tanaman yang tidak terendam air tetapi masih dalam keadaan lembab, sehingga asupan oksigen dalam akar tidak hanya dari oksigen terlarut (dissolved oxigen) tetapi juga dari udara yang ada di atas akar. Tanaman akan memperoleh asupan Air, Oksigen dan Nutrisi yang cukup, sehingga tanaman tumbuh secara optimal. Inilah keuntungan dari Sistem NFT, namun untuk mendapatkan itu semua, harus memenuhi persyaratan berikut ini :

a. Aliran air harus seragam

b. Flow Rate masuk tidak boleh terlalu deras

c. Lebar media berupa talang/gully harus cukup lebar untuk menghindari genangan air oleh akar.

d. Dasar media berupa gully/talang harus datar dan tidak melengkung