Bioscience Evidence 2026, Vol.16, No.4, 264-276 http://bioscipublisher.com/index.php/be 267 Algal management requires not only controlling algal biomass but also maintaining a reasonable ecological structure. The introduction of plants and filter-feeding animals can regulate nutrient cycling in ponds and reduce the risk of excessive algal proliferation. The key point of transparency and algal management is not simply reducing algal quantity, but maintaining a certain level of primary productivity while preventing nutrient over-enrichment and algal community imbalance. 3 Pond Environmental Management of Macrobrachium rosenbergii 3.1 Aeration management The main sources of oxygen in ponds include photosynthesis by algae and aquatic plants, as well as oxygen input from mechanical aeration equipment. Meanwhile, oxygen is continuously consumed by prawn respiration, microbial decomposition of organic matter, and sediment oxygen demand. Although mechanical aeration can rapidly increase dissolved oxygen levels, the oxygen diffusion capacity in the bottom layer of ponds is limited. Therefore, relying only on surface aeration equipment is often insufficient to completely solve low oxygen problems in bottom waters. In practical aquaculture, aeration equipment should be properly configured according to pond depth, stocking density, and water quality changes. Regarding aeration strategies in M. rosenbergii ponds, Sheng et al. (2023) compared pond depths of 1.2 m and 1.8 m and analyzed the effects of traditional surface aeration and combined surface-bottom aeration systems on water environmental conditions. The deeper pond system combined with both surface and bottom aeration effectively improved pond ecological conditions. Compared with the traditional mode, this approach significantly reduced the dominance of cyanobacteria and increased phytoplankton community diversity, with phytoplankton species numbers increasing by 30.43%~136.84%. Under this system, total nitrogen, ammonia nitrogen, total phosphorus, and active phosphate concentrations in the water were also reduced. 3.2 Microbial regulation During high-density M. rosenbergii farming, uneaten feed, feces, and dead biological residues continuously enter the water and release large amounts of nitrogen-containing compounds during decomposition. If these substances cannot be effectively transformed, ammonia nitrogen and nitrite accumulation may occur. Biofloc Technology (BFT) uses microbial communities in water to convert inorganic nitrogen from feed residues and excretion products into microbial protein, while forming natural feed particles that can be utilized by prawns. However, in practical production, the performance of biofloc systems is affected by carbon source input, microbial maturity, and stocking density. Water quality improvement cannot be achieved simply by adding microorganisms. Under different stocking densities, Ly et al. (2024) evaluated the effects of the red algae (Gracilaria tenuistipitata)-biofloc system on water quality and juvenile growth. With increasing stocking density, total ammonia nitrogen (TAN), nitrite, heterotrophic bacteria, and Vibrio populations showed increasing trends. However, under the combined effects of biofloc and red algae, water quality indicators remained within suitable ranges for aquaculture. Among the tested treatments, a stocking density of approximately 1 500 individuals/m³ achieved better overall farming performance. Probiotics are also an important approach for microbial regulation. A biofloc system based on Lactococcus lactis showed that although probiotic addition did not significantly alter the microbial community structure of the water or M. rosenbergii intestine, combining probiotics with biofloc improved farming performance, achieving 100% survival and increasing final body weight (Kathia et al., 2022). Attached microbial communities can absorb ammonium salts and phosphate from water while forming stable microbial structures, providing additional natural nutrient sources for cultured animals (Sow et al., 2024). 3.3 Feeding reduction and waste control With increasing stocking density, feed input continues to rise to meet the rapid growth requirements of prawns. However, uneaten feed and prawn excretion enter the water and are decomposed by microorganisms, producing metabolic products such as ammonia nitrogen and nitrite. When the self-purification capacity of ponds is insufficient, these substances accumulate and cause water quality deterioration. Therefore, reasonable control of
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