Physicochemical and bacteriological screening of pathogenic microorganisms from aquarium water collected from katabon area in Dhaka city

Globally, the ornamental fish business has a high demand for its popularity as well as for its profitability. However, microbial contamination, nutrient depletion and accumulation of organic materials are the major factors in an aquafarming system which can cause death of aquatic animal and causes financial losses. This study aimed to determine the physicochemical and microbiological quality of fish aquarium water. Water of different time interval after treatment (7 days, 20 days, 30 days, 60 days, 90 days) were taken from the different aquariums. A set of physicochemical parameters such as temperature, transparency, pH, conductivity, dissolved oxygen, total dissolved solids, alkalinity, total hardness, conductivity were found within the approved standard concentration for fish. The present study also reveals the microbiological status of the aquaculture water where the total viable count ranging from 2.20×104 to 4.20×104 cfu/ml. Escherichia coli, Staphylococcus spp., and Pseudomonas spp. were present in all samples. Antimicrobial susceptibility tests were also done to determine the antibiotic resistance pattern of microbes isolated from aquarium water. Stamford Journal of Microbiology, Vol.11 (1) 2021: 20-23

Impact of Indian almond leaves on aquarium water quality

There are very few studies done to understand the impact of Indian almond leaves (IAL) on aquarium water quality. Therefore, in this study, Indian almond leaves (IAL) were used to investigate the impacts on water quality in an aquarium with Betta fish as they are hardy fish, tolerant to changes in water quality, comparatively cheaper and more readily available in tropical countries. For this study, the powdered form of IAL was used for faster dilution or mixing. As for the aquarium tank, smaller tanks with a capacity of 4.5 litres are used since Betta fish is small in size and it is easy to be accommodated in the aquarium. The various dosage of IAL in power form (0-200 mg/L) was used to determine physical, chemical and biological parameters of aquarium water quality in the presence of Betta fish. The parameters were Biochemical Oxygen Demand (BOD5), Dissolved Oxygen (DO), turbidity, pH, chlorine and survivability test and tests were conducted on day 1, 3, 7, 14, 21 and 28. All experiments had an increasing value of DO until Day 21 and gradually decreased, while BOD5 increased with increased IAL dosage. Ammonia concentration increased between day 5-10 and then started to decline at day 21 and pH values were decreasing with increased IAL dosage. The total coliform test has the highest total coliform count on day 28 for IAL dosage. The study revealed that Betta fish could survive for 28 days without any application of de-chlorinator. The optimum dosage of 50 mg/L of IAL can eliminate any requirement for de-chlorination for Betta fish.

SMART AQUARIUM BASED MICROCONTROLLER

Indonesia is an endemic area for the spread of one of the most popular ornamental fish, namely the largest betta fish in the world. In exploring their hobbies such as raising ornamental fish such as betta fish, efficient and automatic tools are more needed by betta fish farmers in aquariums today, when they have no free time or are drained by other work. This study aims to be a more automatic and efficient tool for everyone to feed fish, provide lighting, and drain aquarium water automatically, so that owners of ornamental fish do not have to worry about what ornamental fish need in the aquarium. The feeding system, in this case uses an Arduino-based control that controls the servo motor as an open and close system as the exit of fish feed into the aquarium. Aquarium lighting system, in this system uses a light sensor type LDR (Light Dependent Resistor). Automatic aquarium drain system, controlled by Arduino with water pump output. In the research, the LDR sensor will give a signal to the relay and give output to the 220 V lamp, that is, if the light intensity is below 028.7 Lux, which is above half past 6 pm and will turn off the 220 volt lamp if the light intensity is above 203.4 Lux, which is above 6 am. The servo motor will operate twice a day for feeding according to the betta fish feed needs, which is 2 times a day. The water pump will work every 4 days to drain the water automatically according to the turbidity of the water based on the time and number of betta fish in the aquarium.

Transgenes of genetically modified animals detected non-invasively via environmental DNA

We demonstrate that simple, non-invasive environmental DNA (eDNA) methods can detect transgenes of genetically modified (GM) animals from terrestrial and aquatic sources in invertebrate and vertebrate systems. We detected transgenic fragments between 82–234 bp through targeted PCR amplification of environmental DNA extracted from food media of GM fruit flies (Drosophila melanogaster), feces, urine, and saliva of GM laboratory mice (Mus musculus), and aquarium water of GM tetra fish (Gymnocorymbus ternetzi). With rapidly growing accessibility of genome-editing technologies such as CRISPR, the prevalence and diversity of GM animals will increase dramatically. GM animals have already been released into the wild with more releases planned in the future. eDNA methods have the potential to address the critical need for sensitive, accurate, and cost-effective detection and monitoring of GM animals and their transgenes in nature.

Efficacy of acriflavin chloride and Melaleuca alternifolia extract against Saprolegnia parasitica infection in Pterophyllum scalare

The article describes cases of saprolegniosis in Pterophyllum scalare in private aquaristics and assesses the therapeutic efficacy of acriflafin chloride against Saprolegnia parasitica infection. To establish the diagnosis, the clinical signs present in sick fish, the results of mycological and microscopic examinations are taken into account. Some chemical and mycological indices of aquarium water have been studied, and also mycological studies of fish feed have been carried out. It is established that the disease of fish develops against the background of adverse changes in physical, chemical composition and microbiocenosis of aquarium water. Low water temperature, high levels of phosphates and pH, a significant level of organic pollution, compared to the norm, provoke the accumulation of opportunistic microbiota, resulting in imbalance in the parasite-host system and the development of clinical manifestations of saprolegniosis in fish. It was found that 44.4% of the studied feed samples fed to fish were contaminated with epiphytic micromycetes. Micromycetes are represented by the genera Aspergillus, Penicilium, Fusarium, Mucor, Rhizopus. Among the studied feeds, the most affected by fungi were larvae of Chironomus plumosus and dry Daphnia pulex. According to the results of our studies during outbreaks of saprolegniosis, the pH of aquarium water was 8.1 ± 0.7, the content of phosphates – 5.6 ± 1.1 mg/L, micromycetes – 18.0 ± 1.2 CFU/100 cm3. Aspergillus flavus, A. niger and Penicillium canescens were detected in the studied water samples. With saprolegniosis, the angelfish have a reduced appetite, spots, ulcers, white thin threads, and a cotton-like plaque appear on certain areas of the skin, fins, eyes, and gills. It is established that effective means for the treatment of sick fish are external use in the form of a long bath of acriflavine chloride and extract of Melaleuca alternifolia. It is also effective to increase the water temperature to 25–27 °С, to ensure the normative fish-holding density in aquariums and to exclude from the diet fish feed contaminated with micromycetes. After using the drugs for two weeks every other day, water was replaced by 20% of the aquarium volume and aerated. As a result of the treatment, gradual healing of skin lesions and recovery of 65% of fish with signs of lesions of the outer coverings were registered. Thus, the article analyzes the causes of saprolegniosis in angelfish common in private aquariums, describes the clinical signs of the disease and assesses the therapeutic efficacy of acriflavine chloride and Melaleuca alternifolia extract against Saprolegnia parasitica infection. Prospects for further research lie in search of more effective and environmentally friendly means for the treatment of saprolegniosis in aquarium fish.

Aquarium Water Quality Monitoring Based On Internet Of Things

Guppy fish is one type of ornamental fish that is widely kept in aquariums. Water temperature, water pH, and water turbidity are important factors for the life and development of guppy fish in an aquarium. The ideal water conditions for guppy fish in the aquarium are 23-27oC, a pH value of 6.5-7.5, and a water turbidity level of 0-25 NTU. To maintain ideal water conditions, research is needed to keep the aquarium water conditions stable. The research was conducted by experimenting using the NodeMCU platform as a microcontroller and the DS18B20 temperature sensor for sensing water temperature, a pH sensor 4502C, and a TDS sensor for sensing water turbidity. Testing is done by detecting the condition of the aquarium water with all sensors simultaneously to find out the water conditions in real time. The test results show that the tool designed is able to maintain water temperature at 23-27 oC, maintain pH values at 6.5-7.5, and water turbidity at 0-25 NTU. Thus the tool is able to maintain the ideal aquarium water quality for guppies.

Where does it go? The fate of thiocyanate in the aquarium water and blood plasma of Amphiprion clarkii after exposure to cyanide

ABSTRACTThe illegal practice of cyanide fishing continues to damage coral reef ecosystems throughout the Indo-Pacific. To combat this destructive fishing method, a simple, reliable test to detect whether or not a fish has been captured using cyanide (CN) is needed. This study analyzed the toxicokinetics of acute, pulsed CN exposure as well as chronic exposure to thiocyanate (SCN), the major metabolite of CN, in the clownfish species, Amphiprion clarkii. Fish were pulse exposed to 50 ppm CN for 20 or 45 seconds or chronically exposed to 100 ppm SCN for 12 days. Blood plasma levels of SCN were measured following derivatization to SCN-bimane using an Acquity UPLC I-Class and Q-Exactive hybrid Quadrupole-Orbitrap HRAM mass spectrometer or directly by HPLC-UV. After exposure to CN, depending on the duration of exposure, SCN plasma levels reached a maximum concentration (300–470 ppb) 0.13–0.17 days after exposure, had a 0.1 to 1.2 day half-life, and often did not return to baseline levels. The half-life of plasma SCN after direct exposure to SCN was found to be 0.13 days, similar to the CN exposure, and that SCN in the holding water would often drop below detection. Finally, we observed that when a fish, never exposed to SCN, was placed in aquarium water spiked with SCN, there was a steady decrease in aqueous SCN concentration over 24 hours until it could no longer be detected. This pattern was repeated with a second sequential dose. These results demonstrate that A. clarkii do not excrete SCN after CN exposure, but in fact can absorb low concentrations of SCN from water, refuting several publications. It appears that A. clarkii exhibit a classic two compartment model where SCN is rapidly eliminated from the blood plasma and is distributed throughout the tissue but not excreted in their urine. This study demonstrates that SCN may be used as a marker of CN exposure only if fish are tested shortly after exposure. There is species specific variability in response to CN, and studies of other taxa need to be performed before this test can be deployed in the field.

INFLUENCE OF UV RADIATION ON THE TRANSFORMATION OF MONOAND DICHLORAMINES IN WATER OF SWIMMING POOLS IN FULL-SCALE TESTS AND IN THE EXPERIMENT

Introduction. The use of chlorine-containing reagents for disinfection of water in swimming pools may lead to the formation of chloramines, both worsening the organoleptic properties of water and affecting the health of swimmers. To reduce the content of chloramines in pool water, UV radiation can be used. The aim of work is investigation of the effect of UV radiation on the transformation of mono- and dichloramines in water. Material and methods. The study was conducted on water samples from children’s pools, as well as in a model experiment on aquarium water with sodium hypochlorite added. Samples were irradiated with ultraviolet at doses of 40, 80 and 120 mJ/cm2. Before and after UV treatment, the content of chloramines was determined in all samples. Results. UV dose 40 mJ/cm2 was found to be insufficient for the destruction of mono- and dichloramine in water. During UV treatment with a dose 80 mJ/cm2 a decrease in the content of monochloramines and an increase in the content of dichloramines were observed. These processes were depended on the initial concentration of active chlorine in the samples. Conclusion. Thus, an effective UV dose to reduce the concentration of monochloramines in water with a concentration of active chlorine of 0.5 mg/l is 80 mJ/cm2. However, standard UV equipment used for disinfection of pool water cannot guarantee a reduction of chloramine concentration as it is usually designed for the minimum required UV dose (25-40 mJ/cm2). In addition, the effect of UV at this dose on water with a high content of active chlorine led to a significant increase in the content of dichloramines, which is supposedly associated with the destruction of proteins in water under the influence of UV radiation and the subsequent reaction of amino acids with active chlorine.

Influence of UV radiation on the transformation of mono- and dichloramines in water of swimming pools in full-scale tests and in the experiment

Introduction. The use of chlorine-containing reagents for disinfection of water in swimming pools may lead to the formation of chloramines, both worsening the organoleptic properties of water and affecting the health of swimmers. To reduce the content of chloramines in pool water, UV radiation can be used. The aim of work is investigation of the effect of UV radiation on the transformation of mono- and dichloramines in water. Material and methods. The study was conducted on water samples from children’s pools, as well as in a model experiment on aquarium water with sodium hypochlorite added. Samples were irradiated with ultraviolet at doses of 40, 80 and 120 mJ/cm2. Before and after UV treatment, the content of chloramines was determined in all samples. Results. UV dose 40 mJ/cm2 was found to be insufficient for the destruction of mono- and dichloramine in water. During UV treatment with a dose 80 mJ/cm2 a decrease in the content of monochloramines and an increase in the content of dichloramines were observed. These processes were depended on the initial concentration of active chlorine in the samples. Conclusion. Thus, an effective UV dose to reduce the concentration of monochloramines in water with a concentration of active chlorine of 0.5 mg/l is 80 mJ/cm2. However, standard UV equipment used for disinfection of pool water cannot guarantee a reduction of chloramine concentration as it is usually designed for the minimum required UV dose (25-40 mJ/cm2). In addition, the effect of UV at this dose on water with a high content of active chlorine led to a significant increase in the content of dichloramines, which is supposedly associated with the destruction of proteins in water under the influence of UV radiation and the subsequent reaction of amino acids with active chlorine.