Changes

The chemical nutrients to be dissolved in the water can be derived entirely synthetically, or entirely organically, or some combination of both.  Modern industrial growing systems usually include dosing machines which measure the nutrient level and pH in the solution, and add nutrients or pH balancers as required.

The chemical nutrients to be dissolved in the water can be derived entirely synthetically, or entirely organically, or some combination of both.  Modern industrial growing systems usually include dosing machines which measure the nutrient level and pH in the solution, and add nutrients or pH balancers as required.

The roots of the plants are supported in some form of inert or semi-inert medium.  One of the oldest media is simple sand, which was inexpensive and easy to obtain.  Scoria (a volcanic rock) and expanded clay balls have also been used, but their excessive weight is a disadvantage.  There are other mineral-based media which are more advantage, having been heat treated to modify the physical structure.  Perlite and vermiculite are manufactured by the high temperature treatment and expansion of aluminium silicate and mica respectively.  Horticultural rockwool is manufactured by heating a mixture of basalt, limestone and silica to 1600 degrees celsius and then spinning the molten slag into fibres.  Other popular media, particularly in less developed locations, are coir (coconut husk) and peanut hulls.  All of these media function to support the root structures of the plans while allowing them to contact the nutrient solution.

The roots of the plants are supported in some form of inert or semi-inert medium.  One of the oldest media is simple sand, which was inexpensive and easy to obtain.  Scoria (a volcanic rock) and expanded clay balls have also been used, but their excessive weight is a disadvantage.  There are other mineral-based media which are more advantage, having been heat treated to modify the physical structure.  Perlite and vermiculite are manufactured by the high temperature treatment and expansion of aluminium silicate and mica respectively.  Horticultural rockwool is manufactured by heating a mixture of basalt, limestone and silica to 1600 degrees Celsius and then spinning the molten slag into fibres.  Other popular media, particularly in less developed locations, are coir (coconut husk) and peanut hulls.  All of these media function to support the root structures of the plans while allowing them to contact the nutrient solution.

The simplest hydroponic systems do not recycle the nutrient solution, but instead allow it to run off.  These are not very efficient, but are suitable for domestic gardening.  The nutrient solution can act as a true "complete fertiliser" when allowed to run to a lawn or garden.

The simplest hydroponic systems do not recycle the nutrient solution, but instead allow it to run off.  These are not very efficient, but are suitable for domestic gardening.  The nutrient solution can act as a true "complete fertiliser" when allowed to run to a lawn or garden.