computers Review Recent Advancement of the Sensors for Monitoring the Water Quality Parameters in Smart Fisheries Farming Fowzia Akhter 1,*, Hasin Reza Siddiquei 1, Md Eshrat E. Alahi 2 and Subhas C. Mukhopadhyay 1 1 Department of Engineering, Macquarie University, Sydney NSW 2109, Australia; [email protected] (H.R.S.); [email protected] (S.C.M.) 2 Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; [email protected] * Correspondence: [email protected] Abstract: Water quality is the most critical factor affecting fish health and performance in aquaculture production systems. Fish life is mostly dependent on the water fishes live in for all their needs. Therefore, it is essential to have a clear understanding of the water quality requirements of the fish. This research discusses the critical water parameters (temperature, pH, nitrate, phosphate, calcium, magnesium, and dissolved oxygen (DO)) for fisheries and reviews the existing sensors to detect those parameters. Moreover, this paper proposes a prospective solution for smart fisheries that will help to monitor water quality factors, make decisions based on the collected data, and adapt more quickly to changing conditions. Keywords: water quality; fisheries; sensors; IoT Citation: Akhter, F.; Siddiquei, H.R.; Alahi, M.E.E.; Mukhopadhyay, S.C. Recent Advancement of the Sensors 1. Introduction for Monitoring the Water Quality Water contamination is a significant problem worldwide, and it is essential to monitor Parameters in Smart Fisheries the contaminating ions to keep the water safe regularly. Moreover, fresh water and marine Farming. Computers 2021, 10, 26. water fisheries contribute significantly to various countries such as Australia, Vietnam, https://doi.org/10.3390/computers Japan, and the Philippines [1]. It is accepted worldwide that good water quality must 10030026 maintain viable aquaculture production and compete with the growing aquaculture indus- try [2]. The poor water quality outcomes result in inferior quality products, health risks for Academic Editor: George K. Adam humans, and low profit. Water contaminants harm the growth, development, reproduction, and mortality of the fishes cultured on a farm, which vastly reduces farm production [3]. Received: 1 February 2021 Some pollutants may remain in small quantities but may threaten human health [4]. Accepted: 22 February 2021 The fishes breathe, excrete waste, feed, reproduce, and maintain salt balance inside Published: 27 February 2021 the water they live in [5]. Hence, maintaining water quality is the key to ensure the success and failure of an aquaculture project. It is necessary to have a guideline for the farmers on Publisher’s Note: MDPI stays neutral the essential water quality factor and any parameters’ safe level. Otherwise, continuous with regard to jurisdictional claims in published maps and institutional affil- water quality degradation because of anthropogenic sources would reduce the farm’s iations. productivity and profit [6,7]. Therefore, control and management of water quality in water resources are pivotal for both fresh water and marine aquaculture. The water quality of fisheries can be controlled by monitoring the water quality pa- rameters such as temperature, pH, nitrate, phosphate, calcium, magnesium, and dissolved oxygen regularly using sensors. Inclusion of the Internet of Things (IoT) and communica- Copyright: © 2021 by the authors. tion technology with the sensors will bring significant advantages to monitoring the farm Licensee MDPI, Basel, Switzerland. even from a remote location. Suppose the collected data are stored in a cloud server and This article is an open access article distributed under the terms and shared with experts. In that case, the farmers can receive expert feedback from anywhere conditions of the Creative Commons globally, irrespective of their time and location. Figure1 shows a typical diagram of smart Attribution (CC BY) license (https:// fisheries. That is why, nowadays, agricultural countries such as Australia, New Zealand, creativecommons.org/licenses/by/ Japan, and the USA are interested in incorporating agriculture with technology. This 4.0/). Computers 2021, 10, 26. https://doi.org/10.3390/computers10030026 https://www.mdpi.com/journal/computers Computers 2021, 10, x FOR PEER REVIEW 2 of 20 Computers 2021, 10, 26 2 of 20 New Zealand, Japan, and the USA are interested in incorporating agriculture with tech- nology. This necessitates a clear understanding of the vital water quality factors, their im- necessitatespact, and the a cleardevelopment understanding of smart of systems the vital that water can quality be used factors, by the theirfarmers impact, with andminimal the developmenttraining. of smart systems that can be used by the farmers with minimal training. FigureFigure 1. 1.A A typical typical diagram diagram of of smart smart fisheries. fisheries. ThisThis review review article article discusses discusses the the parameters parameters of of deciding deciding water water quality, quality, the the optimum optimum requirementrequirement for for various various fishes, fishes, and and sensors sensors associated associated with with those those parameters. parameters. This This paper paper alsoalso reviews reviews the the software software related related to to water water quality quality management management and and related related research research and and discussesdiscusses those those algorithms’ algorithms’ advantages advantages and and disadvantages. disadvantages. Moreover,Moreover, it it also also proposes proposes a a low-cost,low-cost, low-power low-power system system as aas solution a solution to smart to smart farming. farming. Access toAccess real-time to real-time data through data IoT-enabledthrough IoT-enabled sensors will sensors allow will farmers allow to farmers identify to issues identify affecting issues farms’affecting conditions farms’ condi- and maketions decisionsand make to decisions improve productivityto improve productivity efficiently. Due efficiently. to the collection Due to ofthe a collection large amount of a oflarge data, amount predicting of data, situations predicting is alsosituations possible is also to ensurepossible that to ensure farmworkers that farmworkers are engaged are mostengaged productively. most productively. 2.2. Factors Factors Deciding Deciding Water Water Quality Quality and and Related Related Sensors Sensors TheThe essential essential parameters parameters definingdefining water water quality quality areare water water temperature, temperature, pH, pH, nitrate, nitrate, phosphate,phosphate, calcium, calcium, magnesium, magnesium, and and dissolved dissolved oxygen. oxygen. Numerous Numerous studies studies have have been been car- car- riedried out out on on detecting detecting and and measuring measuring the the amount amount of of those those parameters. parameters. These These are are discussed discussed in this section. in this section. 2.1. Water Temperature 2.1. Water Temperature Fishes are poikilothermic animals whose body temperatures are almost the same as the waterFishes temperature are poikilothermic they live animals in [8]. Water whose temperature body temperatures and fish metabolism are almost the are same closely as relatedthe water to each temperature other. The they fishes live in in higher [8]. Water temperatures temperature have and a more fish significantmetabolism metabolism are closely thanrelated those to livingeach other. in lower The temperature fishes in higher water temperatures [9]. This applies have toa more warm-water significant fishes. metabo- The optimumlism thantemperature those living in range lower for temperature tropical water water fish [9]. is 24~27This applies◦C, whereas to warm-water for cold-water fishes. fishThe it optimum is below temperature 20 ◦C. Cold-water range for fishes tropical such wa aster whitefish, fish is 24~27 salmonids, °C, whereas and burbot for cold-wa- have higherter fish metabolism it is below 20 at °C. a lower Cold-water temperature. fishes such They as become whitefish, less salmonids, active due and to consumingburbot have lesshigher food metabolism at a temperature at a lower above temperature. 20 ◦C. Fish They diseases become may less initiate active and due spread to consuming because less of waterfood at temperature a temperature [10 ].above Different 20 °C. fishes Fish diseases require may different initiate temperatures and spread because for their of health water andtemperature wellbeing. [10]. These Different are summarised fishes require in Table different1[ 11 temperatures]. Most of the for fishes their have health the and highest well- immunitybeing. These at a are temperature summarised of about in Table 15 ◦1C. [11]. Fishes Most naturally of the fishes adapt have to seasonal the highest changes immunity such as,at ata temperature 0 ◦C in the winterof about and 15 20°C.◦ CFishes to 30 naturally◦C in the adapt summer. to seasonal However, changes the temperature such as, at 0 should°C in the not winter change and abruptly 20 ℃ asto fishes30 °C arein the shocked summer. if they However, are put inthe a temperature new environment should with not achange temperature abruptly change as fishes of 12 are◦C shocked than the if original they are water put in [12 a, 13new]. Fishesenvironment may be with paralysed a tem- orperature die under change these of circumstances. 12 °C than the Theoriginal young water fry [12,13]. may show Fishes these may symptoms, be paralysed