Effects of formaldehyde bisulfite sodium on the reduction of nitrogen compounds in the tanks, hematology, and immunity of Cyprinus rubrofuscus

It is well known that ammonia nitrogen is a major pollutant in aquaculture, which can have toxic effects on fish. When absorbed in toxic concentrations, ammonia nitrogen can enter the bloodstream of fish, affecting blood parameters, immune responses, and causing oxidative damage and neurotoxicity. Recently, a study was conducted to investigate the toxic effects of ammonia on the blood, liver, growth, tissue damage, and immune indices of Cyprinus rubrofuscus in the presence of formaldehyde bisulfite sodium (FBS). The study involved 360 C. rubrofuscus, which were randomly distributed among 24 aquaria with a ratio of FBS to ammonia set at 31mg/L:1mg/L. The experiment was conducted with 15 fish in 6 treatments and 4 repetitions until 50% mortality was observed. The growth, histology, hematology, immunity, liver enzymatic and biochemical features of the fish were studied, and the results were analyzed using one-way analysis of variance (One-Way ANOVA) and Duncan’s test. The study found that the blood, immune, and liver indices of koi fish changed in the presence of FBS. Additionally, adding FBS to aquarium water reduced nitrogen compounds in fish storage tanks, further reducing the nitrogen compounds in fish aquaria.