**8. Conclusion**

Hydroponic cultivation is revolutionizing agricultural crop production techniques all over the world owing to its minimal environmental footprint, enhanced pest control, and provide high crop yield. It allows more accurate control of environmental conditions that offer possibilities for increasing production and improving the quality of crops. The rapid development of computers and controllers has enabled the opportunity to apply the controller in hydroponics. The microcontroller could be used to control these nutrient solution parameters by using relevant sensors. It monitors the conductivity and pH throughout 24 h during the whole cycle of production. Also, it helps in monitoring temperature, nutrient atomization, EC, and pH fluctuations and level of nutrient solution in the nutrient reservoir. However, although the comprehension of the multi-level interactions among the various mineral elements is considered

crucial to understanding the different sensing and signaling pathways induced by a single or multiple shortage/s, the impact of these nutrients' interactions on crop performance is largely unknown [32].

Some hydroponic growers use more than the required amounts of nutrients for crop growth to minimize the chances of nutrient deficiency. But one of the most important factors for a successful hydroponics system is the use of the appropriate nutrient solution, and it is important to control the amount of nutrients to allow or deny plants the nutrient accumulation. While hydroponic systems are considered to represent a sustainable method for growing plants, the nutrient solution used in hydroponic systems is based on chemical fertilizers which are mined from scarce and non-renewable resources. Recently, there has been an increased interest in organic hydroponics, as the market for organic food continues to grow and some studies have reported the possibility of growing vegetables using an organic nutrient solution. For optimizing the utilization of organic waste for hydroponic plant growth, a solubilization step is required to break down organic matter and mobilize nutrients [96]. For example, the direct use of organic fertilizers in hydroponic systems may inhibit plant growth due to the high biological oxygen demand in the root zone caused by the presence of dissolved organic carbon compounds. Additionally, most of the nutrients in organic sources, such as waste material from the agricultural and aquacultural industry, are not in ionic forms and, hence, are not directly available for plants. Also, the last decade has seen increasing interest in using wastewater as a source of hydroponic nutrition. This aims at a dual benefit of optimizing water reuse as well as a practical end point for wastewater management. Untreated domestic rinse water obtained from washing machine second-cycle rinse can effectively be used for indoor hydroponic cultivation of plants without the need for any additional fertilizer. It also entails the benefits of significant savings in water use, sewage disposal, ecosystem protection, and the possibility to produce economically viable food crops [97]. Nowadays, hydroponic farming technology is extensively used in producing ornamental plants and flowers. Controllable application of fertilizers, the ability to change nutrients in different weather conditions and different plant growth stages, reduction of fertilizer leaching from the root zone, reduction of contamination, environmental protection, and enhancement of the quality and quantity of products are becoming some of the advantages of this technology.
