Effectiveness Probiotic of Nitrosomonas sp. and Bacillus sp. in Improving the Water Quality and Growth of Tilapia Larasati (Oreochromis niloticus)

Aquaculture plays a critical role in global seafood production. Probiotics in aquaculture have gained popularity for enhancing fish health, growth, and water quality. This study aimed to evaluate the effects of probiotic supplementation through different methods-feed and/or water-on Nile tilapia's growth, health, and resistance to Aeromonas hydrophila. A total of 270 Nile tilapia fingerlings (initial weight 10 ± 05 g) were randomly divided into four experimental groups: (1) control group (basal diet with no probiotics), (2) feed additive group (basal diet + probiotics in feed), (3) water additive group (basal diet + probiotics in water), and (4) combined feed and water additive group (basal diet + probiotics in both feed and water). The trial lasted for 12 weeks. The study assessed water quality, growth performance, feed efficiency, digestive enzyme activities, intestinal morphometry, biochemical and immunological parameters, oxidative status, and resistance to A. hydrophila. The results revealed significant improvements in water quality (reduction in TAN and NH3), growth performance, feed utilization, digestive enzyme activity (amylase, lipase), and immune responses in all probiotic-treated groups compared to the control. The group receiving probiotics in both feed and water showed the highest growth, survival rate, and immune function improvements. Additionally, gene expression analysis revealed upregulation of immune-related cytokines (IL-1β, TGF-β, TNF-α) in this group. In conclusion, administering probiotics via both feed and water significantly enhances Nile tilapia's health, growth, and resistance to bacterial infections, with the combined approach yielding the best results. This study highlights the importance of optimizing probiotic administration methods to maximize benefits in aquaculture systems.

Nile tilapia (Oreochromis niloticus) is one of the leading aquaculture commodities in Indonesia, valued for its high economic potential and growing market demand. The success of tilapia farming is highly influenced by optimal water quality, particularly the level of dissolved oxygen (DO), which plays a crucial role in supporting the metabolic and physiological processes of the fish. One commonly used technology to maintain DO levels is the diffusion aerator system, whose efficiency is strongly affected by the design and diameter of the diffuser. This study aimed to analyze the effect of diffuser diameter variation on water quality and tilapia growth performance, and to determine the most effective diameter for maintaining optimal rearing conditions. The experiment was conducted over 45 days using a completely randomized design (CRD) consisting of six treatments and three replications: (A) stone aerator (control), and custom-made diffusers constructed from used tires with diameters of (B) 1 inch, (C) 2 inches, (D) 3 inches, (E) 4 inches, and (F) 5 inches. Observed water quality parameters included temperature, pH, DO, ammonia, nitrite, and alkalinity. Growth performance indicators measured included specific growth rate (SGR), daily feed intake, feed conversion ratio (FCR), and survival rate. The results indicated that all treatments-maintained water quality within optimal ranges for tilapia culture. However, no significant differences (p > 0.05) were observed in growth performance across treatments. These findings suggest that tire-based diffusers can serve as effective, economical, and environmentally friendly alternatives to conventional aeration systems in tilapia aquaculture. Keywords: Aeration; Aquaculture; Assembled Diffuser; Fish Growth; Nile Tilapia; Water Quality

Aquaculture plays a critical role in global food production, with tilapia being a highly adaptable species capable of thriving in high-density environments. However, poor water quality in intensive aquaculture systems negatively impacts fish health and production. Excessive waste accumulation leads to increased levels of ammonia, nitrite, and nitrate, posing significant risks to both fish and environmental sustainability. Phototrophic sulfur bacteria (PSB) have been recognized for their ability to remove nutrients, heavy metals, and organic pollutants, offering a sustainable approach to wastewater treatment in aquaculture. This study evaluates the efficacy of isolated PSB compared to commercially available PSB in improving water quality in red hybrid tilapia (Oreochromis spp.) culture systems. A controlled laboratory experiment was conducted with three treatment groups: a negative control (T1), a positive control with commercial PSB (T2), and an experimental group with isolated PSB (T3). Key water quality parameters—including ammonia, nitrite, nitrate, pH, dissolved oxygen (DO), turbidity, total dissolved solids (TDS), conductivity, and temperature—were monitored at seven-day intervals over two months. Growth performance was assessed based on weight gain, specific growth rate (SGR), survival rate, and feed conversion ratio (FCR). Statistical analysis using ANCOVA determined significant treatment effects. Results showed that the isolated PSB-treated tank achieved a substantial reduction in ammonia (from 8.0 to 1.0 ppm), nitrite (from 5.0 to 0.3 ppm), and nitrate (from 160.0 to 5.0 ppm). The pH remained stable (6.5–7.5), turbidity and TDS decreased, and DO levels exceeded 5.0 mg/L, indicating improved water quality. Growth performance in the isolated PSB group was superior, with significantly higher weight gain and SGR compared to the controls (P < 0.05), suggesting enhanced fish health. The isolated PSB represents a promising, eco-friendly approach for sustainable wastewater treatment in tilapia aquaculture. This study underscores the potential of PSB in optimizing water quality, promoting fish health, and advancing environmentally responsible aquaculture. Future research should focus on large-scale implementation and refining PSB formulations for enhanced commercial viability, suggesting enhanced fish health. The isolated PSB represents a promising, eco-friendly approach for sustainable wastewater treatment in tilapia aquaculture. This study underscores the potential of PSB in optimizing water quality, promoting fish health, and advancing environmentally responsible aquaculture. Future research should focus on large-scale implementation and refining PSB formulations for enhanced commercial viability.

Heavy metals (HMs) are one of the emerging micropollutants, which have been found a significant toxicant to the fish fauna; therefore, the current study aimed to examine HMs including Cd, Cr, Pb, and Cu concentrations in sludge and their accumulation in Oreochromis niloticus tissues along with growth and water quality in Biofloc Technology (BFT). Tilapia, initially weighing 0.40 ± 0.15 g, were divided into three groups (G1, G2, and G3) with three replicates each. Sludge was removed weekly for G1, biweekly for G2, and monthly for G3 over 90 days. Water quality parameters were monitored daily, and (HMs)in sludge and fish tissues were analyzed. One‐way ANOVA with multiple comparisons was used to compare the results among groups. Results showed that sludge removal frequency significantly (p < 0.05) affected water quality. G3 had higher ammonia, nitrate, and nitrite levels, and a slightly acidic pH. G1 had higher dissolved oxygen (6.72 mg/l) compared to G3 (5.32 mg/l) and better growth performance with a lower feed conversion ratio (FCR) of 1.44 versus 1.67 for G3. The HM analysis showed that G3 had higher metal concentrations in both fish tissues and sludge, with a strong correlation between metal levels in sludge and fish tissues. The health index (HI) values confirmed that fish from all groups were safe for human consumption. The study concludes that regular sludge management is crucial for optimizing BFT production and safety; therefore, G1 has optimum growth and water quality with less HM accumulation.Practitioner Points Study examines Cd, Cr, Pb, and Cu accumulation in Nile tilapia tissues and sludge under varying sludge removal frequencies. Weekly sludge removal improves water quality, dissolved oxygen, and fish growth, with better FCR. Monthly sludge removal shows higher ammonia, nitrate, nitrite, acidic pH, and metal concentrations in sludge and fish tissues. Strong correlation found between sludge metal levels and fish tissue accumulation. Findings emphasize regular sludge management for enhanced BFT production, safety, and reduced heavy metal bioaccumulation.

Biofertilizer is active biological product contain of microbes. Liquid biofertilizer in aquaculture contains Bacillus sp. The utilization of Bacillus sp. in aquaculture is aimed to keep balancing of microbes in digestive, increasing nutrient absorbtion rate and improving water quality, therefore it can preserve survival rate and growth of fish. The aim of this research was to find out the effect of liquid biofertilizer in media rearing for water quality, survival rate, growth and feed efficiency of nile tilapia. This research was conducted from January to May 2015 at Budidaya Perairan Laboratory, Budidaya Perairan Study Program, Agricultural Faculty, Sriwijaya University, Indralaya. This research used Completely Randomized Design (CRD) with seven treatments. The liquid biofertilizer was in added rearing media every week with different concentrations were 0; 0.5 µl.L -1 ; 1 µl.L -1 ; 1.5 µl.L -1 ; 2 µl.L -1 ; 2.5 µl.L -1 ; 3 µl.L -1 . Parameters observed included water quality, survival rate, growth, and feed efficiency. Liquid biofertilizer addition in water media rearing didn’t show significant role to water quality, and it didn’t significant show different with survival rate, growth, and feed efficiency of tilapia. Additional liquid biofertilizer in 2.5 µl.L -1 dan 3 µl.L - 1 showed the highest survival rate (85%), where as the best concentration of liquid biofertilizer for growth was 1.5 µl.L -1 (4.82 g), and the best concentration of liquid biofertilizer for feed efficiency was 2.5 µl.L -1 (91.8 %). Keywords : Biofertilizer, Bacillus sp, Tilapia

Biofloc technology is an aquaculture production system that has gained popularity with tilapia production. Probiotics provide benefits for the host and/or aquatic environments by both regulating and modulating microbial communities and their metabolites. When a probiotic feed is combined with a biofloc system, the production amount may be improved through better fish growth, disease resistance, and/or improved water quality by reducing organic matter and stabilizing metrics such as pH and components of the nitrogen cycle. Two research trials measured Nile tilapia (Oreochromis niloticus) growth performance and composition of the microbial communities in the water and within the fish fecal material, following feeding with top-coated probiotic treatments. Trial A incorporated tilapia (71.4 ± 4.4 g), and a commercial diet (Control) that was top coated with either Bacillus velenzensis AP193 (AP193; 1 × 107 CFU g1) and BiOWiSH Feedbuilder Syn3 (BW; 3.6 × 104 CFU g-1). In Trial B, juvenile tilapia (5.34 ± 0.42 g) were fed treatment diets top coated with two different concentrations of BiOWiSH Feedbuilder Syn3 at final concentrations of 3.6 × 104 CFU g-1 (BWx1) and 7.2 × 104 CFU g-1 (BWx2). Tilapia were offered commercial feed (38% protein floating tilapia feed) as a control diet for both trials. Results from both growth trials indicated no differences in growth performance due to the probiotic additions, except for feed conversion ratio (FCR) in Trial B. Both BWx1 and BWx2 showed improved survival, water quality, solids management, and bacterial composition of water and fecal matter. Even though growth performance results presented no significant differences, results could differ based on the probiotic concentration, the route of probiotic administration, or their impact on the microbial community of the biofloc system culture water. Trial results indicated that testing on a larger scale with varied probiotic doses may be necessary to achieve an effective dosage for improving tilapia growth performance.

The aims of this study were to examine the effects of phytase enzym and to determine the optimum dose of phytase enzym in artificialfeed on digesting, specific growth rate and survival rate of Nile Tilapia fingerlings (Oreochromis niloticus). Nile Tilapia fingerlings(O. niloticus) used in this study were 120 animals with the weight of 3±0.02 g/animal. The fingerlings were raised in 6 weeks with thedensity of 1 animal/liter. Methodology used in this study was laboratory treatments with complete random design. The studyconsisted of four treatments and three repetitions. The treatments were addition of phytase enzym in artificial feed with the differentlevel of doses; those were A (0 mg/(kg of feed)), B (500 mg/(kg of feed)), C (1.000 mg/(kg of feed)), and D (1.500 mg/(kg of feed)).The artificial feed with 30% protein content was in the dried and crumb pellet form which was added phytase enzym in everytreatment. Data collected were specific growth rate, feed conversion ratio, protein efficiency ratio, raw protein digesting rate, totalprotein digesting rate, survival rate and water quality. Varian annalysis was used in this study. If the results were significant(p<0.05) and highly significant (p<0.01), double Duncan area test was conducted to determine the mean of different treatments. Inorder to find the optimum effect polynomial orthogonal test was used. Descriptive analysis was used to explain raw and total proteindigesting rate and water quality. The results show that the addition of phytase enzym in artificial feed significantly affected on thespecific growth and feed utilization ( feed and protein efficiency ratios); however, it did not significantly affect on the survival rates.The optimum dose of phytase enzym in artificial feed on the specific growth and feed utilization was at the level of 1,000 mg/(kg offeed). This level resulted in the highest of raw and total protein digesting rates of Nile Tilapia fingerlings (O. niloticus), compared toB, D, and A treatments. The raw and total protein digesting rates were of 84.88% and 71.27%. The water quality during study was inviable range for the Nile Tilapia fingerlings (O. niloticus) cultivation.Keywords : Nile Tilapia (Oreochromis niloticus), Phytase Enzym, Digesting, Specific Growth, Survival Rate

This study aimed to evaluate the synergistic effects of Quillaja saponaria (QS) and Yucca schidigera (YS) on water quality, growth performance and health status of Nile tilapia. Fish (n = 120, 11.97 ± 0.497 g) were randomly distributed into four experimental groups in triplicates. (1) Control group (CG), fish received basal diet; (2) Yucca schidigera group (YS); fish received basal diet and 0.11 ml/m3 per week YS extract in water; (3) Quillaja saponaria group (QS), fish received basal diet supplemented with 300 mg/kg QS extract; (4) Mixed group (QS/YS), fish received basal diet supplemented with 300 mg/kg QS and 0.11 ml/m3 per week YS extract in water. Results revealed an improvement of water quality parameters in QS/YS, YS and QS compared with CG (p ≤ 0.05). Fish received QS and/or YS showed higher growth performance and lower feed conversion ratio than CG (p ≤ 0.05), with the best findings being reported in QS/YS. Using QS and/or YS improved gill health, increased intestinal villi length and goblet cell number compared with CG (p ≤ 0.05). Lymphocytes, total protein, globulin and lysozyme activity were increased, while cholesterol, triglycerides, glucose and creatinine were decreased in fish received QS and/or YS compared with CG (p ≤ 0.05), with the best results being observed in QS/YS. QS and/or YS supplementation increased lipase, amylase, superoxide dismutase, catalase while reduced malonaldehyde activity compared with CG, with the highest activity being recorded in QS/YS. Conclusively, Nile tilapia received QS and YS prompted synergistic effects that improved water quality, growth performance, immune-oxidative status, digestive enzymes, gills and intestine histomorphology.

Transportation activities are a major cause of tilapia mortality due to stress induced by long travel, decreased dissolved oxygen, and high levels of ammonia. The addition of guava leaf extract expected to be an alternative solution. This study aimed to analyze the effect of guava leaf extract addition during transport and post-transport rearing on survival rate, water quality, blood glucose, and specific growth rate of tilapia. This study used a completely randomized design of two treatments and one control all in triplicate. Transportation 24 hours and maintenance after transportation 21 days. The results of the study showed more optimal water quality and changes in blood glucose after transport in control 117.33 mg dL −1 , while 0.50% was 87.33 mg dL −1 , which was relatively lower than the control. A 0.50% dose resulted in an increase in survival rate (SR) from 80% in the control group to 90%. After maintenance treatment with extract resulted in an SR of 100%. Specific growth rate in treatments did not have a significant effect. Conclusion is that the addition of guava leaf extract as an environmentally friendly additive at 0.50% of the total water volume used in tilapia significantly affects SR, water quality during transportation, and blood glucose levels in fish after transportation.

The novel coronavirus disease (COVID-19) halted almost all the industrial scale anthropogenic activities across the globe, resulting in improvements in water and air quality of megacities. Here, using Sentinel-2A data, we quantified impact of COVID-19 lockdown on the water quality parameters in one of the largest perennial creeks i.e., the Buddha Nala located in District Ludhiana in India. This creek has long been considered as a dumping ground for industrial wastes and has resulted in surface and ground water pollution in the entire lower Indus Basin. Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Chlorophyll Index (NDCI), Nitrogen Content Index (NI), Normalized Difference Turbidity Index (NDTI), and Total Suspended Matter (TSM) were compared prior (2019) and during (2020) lockdown in the creek. There was a significant enhancement in NDVI, NDWI, NDCI, and NI values, and reduction in NDTI and TSM values during the lockdown period. When compared with prior year (2019), the values of indices suggested an improvement in water quality and an indicative change in aquatic ecology in the creek. The impact of the COVID-19 lockdown on the improvement in water quality of Buddha Nala was more evident in the upstream and downstream sections than the middle section. This is intriguing since the middle section of the creek was continually impacted by domestic household effluents. The earth observation inspired methodology employed and findings are testament to the discriminatory power to employ remote sensing data and to develop protocols to monitor water quality in regions where routine surveillance of water remains cost prohibitive.

The aquaculture sector has experienced disruptions in its ability to feed the expanding population due to the existence of disease outbreaks in Nile tilapia (Oreochromis niloticus) cultivation. Antibiotic treatment in mitigating disease may not be the best alternative because it harms both humans and the environment. To solve this issue, probiotics as a feed supplement seems very promising as an alternative. This research aimed to study the effects of probiotic supplementation Lactiplantibacillus plantarum strain BE7 on the growth and survival of the O. niloticus. In this research, 2 groups were studied, which were the treatment and control groups.Juvenile O. niloticus in the treatment group was fed with fish feed coated with L. plantarum BE7 at a concentration of 1×109 CFU/mL (1 mL/g) while in the control group, the O. niloticus was fed with fish feed only. The feeding was administered with a feeding rate of 5% of the bodyweight twice daily at 09:30 and 15:30 for 35 days. Each group consists of three replicates. The growth performances observed in this research were survival rate, death rate, absolute growth rate of weight, length, and width, specific growth rate (SGR), and feed conversion ratio (FCR). Dissolved oxygen (DO), total dissolved solids (TDS), pH, and temperature were the water quality parameters measured. The results showed that the juvenile O. niloticus fed with probiotic had a better survival rate, and higher absolute growth weight, length and width, as well as, specific growth rate (P>0.05). The treatment group also was recorded a lower death rate and feed conversion ratio compared to the juvenile fed without probiotics. The water quality was observed not affected by the presence of the probiotic in the water. The probiotic supplementation in the O. niloticus diet may help the digestive system of the fish by improving its feed digestibility; therefore, more nutrients are absorbed from fish feed, resulting in higher growth performance. As a conclusion, probiotic diet improves growth and survival of O. niloticus.

Simple SummaryAmmonia is a problematic environmental toxicant for aquatic species. The current study aimed to declare the modulatory effect(s) of YSE against chronic ammonia intoxication in Nile tilapia through its effects on growth performance, haemato-biochemical and antioxidant-related parameters, and histopathological changes, as well as the molecular gene expression of some genes related to appetite and growth, glucose and lipid metabolism and some inflammatory cytokines. Our results indicated that Yucca schidigera extract alleviated the adverse impacts induced by ammonia intoxication. YSE could be used as a functional water supplement in aquaculture.Ammonia is a critical hazardous nitrogen metabolic product in aquaculture. Despite trials for its control, ammonia intoxication remains one of the most critical issues to overcome. In this study, we explored the modulatory effect and potential mechanism by which Yucca schidigera extract (YSE) can ameliorate ammonia intoxication-induced adverse effects on tilapia health and metabolism. A total number of 120 Nile tilapia were evenly assigned into four groups with three replicates each. The first group served as normal control group; the second group was exposed to ammonia alone from the beginning of the experiment and for four weeks. The third group was supplied with YSE in water at a dose of 8 mg/L and exposed to ammonia. The fourth group was supplied with YSE only in water at a dose of 8 mg/L. YSE supplementation succeeded in improving water quality by reducing pH and ammonia levels. Moreover, YSE supplementation markedly alleviated chronic ammonia-induced adverse impacts on fish growth by increasing the final body weight (FBW), specific growth rate (SGR), feed intake and protein efficiency ratio (PER) while reducing the feed conversion ratio (FCR) via improvements in food intake, elevation of hepatic insulin-like growth factor (ILGF-1) and suppression of myostatin (MSTN) expression levels with the restoration of lipid reserves and the activation of lipogenic potential in adipose tissue as demonstrated by changes in the circulating metabolite levels. In addition, the levels of hepato-renal injury biomarkers were restored, hepatic lipid peroxidation was inhibited and the levels of hepatic antioxidant biomarkers were enhanced. Therefore, the current study suggests that YSE supplementation exerted an ameliorative role against chronic ammonia-induced oxidative stress and toxic effects due to its free radical-scavenging potential, potent antioxidant activities and anti-inflammatory effects.

Metagenomic insights into feasibility of agricultural wastes on optimizing water quality and natural bait by regulating microbial loop

Especially in arid regions, developing tilapia culture with the ability to survive a wide range of salinities is crucial due to the limited availability of fresh water for aquaculture. The present study focused on evaluating the growth performance of Nile tilapia in a biofloc system under three salinity levels: 0 (BFT0), 4 (BFT4), and 8 g/L (BFT8). Fingerling fish were raised for 37 days in tanks with a water volume of 140 liters and a stocking density of one fish per liter. The results of the water quality parameters showed that dissolved oxygen and pH decreased with increasing salinity. Furthermore, the BFT8 group had the highest concentrations of settled solid (19.98 ml/L) and total suspended solid (428.37 mg/L), while the BFT8 group had the lowest TAN concentration (4.32 mg/L). The final weight and specific growth rate were significantly higher in the BFT8 and BFT4 groups compared to the BFT0 group. Survival rates were not significantly different across treatments, and all of them were higher than 97%. The protein and lipid content of Nile tilapia bodies and bioflocs decreased with increasing salinity, while the ash content increased. The highest body ash content in Nile tilapia (13.81% of dry weight) and bioflocs (31.78% dry weight) was found at 8 g/L salinity. Based on the present study, it is suggested that salinities of 4 and 8 g/L can improve water quality, growth performance, survival, and carcass composition of Nile tilapia fingerlings in the biofloc system. This finding suggests that brackish waters can be utilized for sustainable aquaculture for the rearing of Nile tilapia.

Water quality in aquaculture has been considered to be an important factor that influences the growth and survival of fish in nursery to growout phase. A microalga, Chlorella vulgaris is utilized to filter chemical substances to maintain optimum water quality and growth of fish. The present study was conducted to know the efficiency of Chlorella vulgaris in maintaining water quality and growth of juvenile Siamese fighting fish (Betta splendens). As nutrient utilization capacity of immobilized microalgae is higher than the free floating microalgae, the experiment was consisted of 4 treatments which were control (blank beads), low (4-5 beads/mL) (T1), medium (10-12 beads/mL) (T2) and high (15-16 beads/mL) (T3) concentration of microalgae beads. It has been found that, in the control treatment, ammonium concentration initially reduced in medium rate (1.5 mg/L to 0.8 mg/L) but become slower (0.8 mg/L to 0.7 mg/L) in later days. But in first four days, reduction of ammonium and nitrite concentration was followed by T3, T2, and T1 and from day five to seven, both were slightly higher than previous day. On the other hand, PO4 3+ showed great reduction (60 mg/L) than the other treatment tanks. Highest SGR found in algal beads containing treatments than control treatment which were recorded as 4.58, 4.61, 4.57 and 3.60 in T1, T2, T3 and control treatment respectively. Results showed that, there was no significant difference (p < 0.05) in TAN, NO2-N, PO4-P, pH, DO and temperature among the microalgae beads containing treatments but significant difference (p < 0.05) found among control and microalgae beads containing treatments. It has been recommended to study economic feasibility of using microalgae beads to maintain the water quality in commercially important ornamental and aquaculture species especially in fish and shrimp hatchery for the larval rearing.