NFT hydroponics, the most popular of all systems around,learn the basics and maybe even build your own hydroponics system.
Plants are placed in this gully’s either in net pots (which I prefer) or in rockwool cubes, once the plants are placed in these gully the roots of the plants have access to all the water oxygen and nutrients that they will require.
NFT hydroponics-Nutrient film technique are an active re-circulating system, where the nutrient solution is pumped up to the gully from the reservoir and flows down past the roots and out the other end and back to the nutrient reservoir.
The gully’s of the system will need to be covered to prevent lights from entering the root zone as this will impede good root growth and will also Encourage algae from growing which will cause problems later on in the growth cycle.
In more resent years spreader mat or soaker mat which is what we called the matting in the nursery, and what its designed is in fact to soak up and retain the excess water in nursery when plants are watered from above, the roots will also grow into the matting and prevent the plants from being toppled over when watered.
Spreader matting can be used in nft hydroponic system to help spreading the water over the entire base of the gully, as ensuring the gully are level can be fairly tricky business and also helps keep larger plants upright, when on a table with lots and lots of other plants.
Because the roots are exposed in this NFT system the plants are very susceptible to temperature and changes in temperature and is very much important than in other systems. Changes in temperature to the nutrients will cause some nutrients to be blocked from being absorbed though the roots, causing. Deficients in the plant, becoming visible though plant development and foliage colour.
Preventing nutrient solution from getting to cold a fish tank heater can be used, plastic moulded heaters are much more practical to use than the traditional glass units, solution should always be kept at 21c
Nutrient and root system getting too hot is not normally not a problem in the northern hemisphere except in enclosed grow rooms, when nutrients do get to hot the soluble oxygen within the solution will dramatically drop if this applies to you then please refer to the home page under (indoor hydroponics).
Aeration in NFT hydroponics systems are normally adequate as when your nutrient solution returns to the tank via the gully and drops into the tank causing irrigation and aeration, although an additional air stone in the tank will do no harm and will help if growing some place that’s fairly warm such as an enclosed area, green house or just a hot spell, oxygen supplement are available in the form of tablets from your local (aquatics centre) or from your hydroponics store in the form of a product called, wait for it, oxyplus who also sell oxygen test strips called, can you guess,oxy-plus test strips, which will tell you the amount of dissolved oxygen of your solution
As a rule of thumb you should change the solution and clean the tank every two weeks, but no more than two weeks, the smaller the tank the more often your solution will require changing
Topping up your solution can be done between solution changes although I only recommend only once before changing solution and cleaning the tank of excess unresolved salts
Fill you tank up with fresh water and only fresh water, when your tank has emptied by one quarter to a half, this is because docent necessarily take up equal quantity of nutrients and water, meaning you could end up with a tank of highly concentrated nutrient solution which is highly toxic to your plants.
Although some solution will automatically adjust your solution its always best to check. After you’ve mixed your solution the ph of the solution after its cycled through the system for half hour. For lots more on why and how to on pH please check out by clicking on the link above.