INTRODUCTION
What is Hydroponics?
Derived from the Latin word meaning ‘working water’, hydroponics is the process of growing plants with added nutrients and water, and without soil. Alternately, plants receive the nutrients through its water supply, which substitutes for the soil’s absence, as a key role of the soil is to help the plant grow, stay healthy and alive with the nutrients it provides. Nutrients are provided by the use of mineral salts, which can be either naturally derived or manmade. They are purified and processed so that they are in a form in which plants can obtain the nutrients found within these mineral salts. As well as this, it must too be water soluble for the plant to be able to absorb the nutrients through the root system.
Nutrients are provided by the use of mineral salts, which can be either naturally derived or manmade. They are purified and processed so that they are in a form in which plants can obtain the nutrients found within these mineral salts. As well as this, it must too be water soluble for the plant to be able to absorb the nutrients through the root system. (Mason, 2009)
Relevant Hydroponic Equations
Most hydroponic experiments require and deal with equations needed to perform the experiments. The following investigation will use equations that will find the molarity of the nutrient solution, the moles of the solute and the dilution formula.
Essential Plan Nutrients
Just like humans, plants need essential nutrients in order to survive. They also assist with growth and reproduction in order to keep them healthy and strong. The nutrients associated with plant life are divided into 3 categories; essential, macronutrients and micronutrients. Macronutrients are then subdivided into primary and secondary nutrients. The first category, essential nutrients, consists of Carbon (C), Hydrogen (H) and Oxygen (O2). These are non-mineral nutrients which also play a large role in photosynthesis: a process in which nutrients are converted to starch and sugar which is a food source for the plants. Plants are usually able get these nutrients from water (H2O) and carbon dioxide (CO­2). The second category is the macronutrients. Macronutrients are basically the nutrients needed in large amounts to help plants sustain life. Primary macronutrients include Nitrogen (N), Phosphorus (P) and Potassium (K). Plants need so much of these nutrients to survive; therefore fertilisers are often added to cover due to the lack of amount found in soil. Secondary nutrients include Calcium (Ca), Magnesium (Mg) and Sulphur (S). Plants too use a large amount of these nutrients; however a mere amount when compared to the amount of primary nutrients needed. This results in fertilisation being unnecessary as the soil provides the appropriate amount needed. (North Carolina Department of Agriculture and Consumer, 2010)

Essential Plant Nutrients and their Functions
Macronutrients- Primary
Nitrogen (N)
Necessary part of all proteins, enzymes and metabolic processes involved in transfer and synthesis of energy
A part of chlorophyll, pigment responsible for photosynthesis
Assists with rapid growth, plant reproduction (seeds and fruit) and improves the quality of the plant
Phosphorus
Essential part of photosynthesis
Involved in oil, sugar and starch formation
Assists with transformation of solar energy to chemical energy, plant maturation and withstanding stress
Effects rapid growth
Boosts blooming and root growth
Potassium
Assists in protein building, quality of fruit, photosynthesis and reduction of disease
Macronutrients- Secondary
Calcium
Essential part of plant cell wall structure
Provides strength for the plant
Counteracts alkali salts and organic acids
Magnesium
Part of chlorophyll and essential for photosynthesis
Activates plant enzymes needed for growth
Sulfur
Essential food plants need for production of protein
Promotes activity and development of enzymes and vitamins
Assists chlorophyll formation
Improves root