Hydrogen peroxide as a mitigation against Microcystis sp. bloom

• Published in: Aquaculture 2023-12, Vol.577, p.739932-739932, Article 739932
• Main Authors: Ng, Pok Him, Cheng, Tzu Hsuan, Man, Ka Yan, Huang, Liqing, Cheng, Ka Po, Lim, Kwok Zu, Chan, Chi Ho, Kam, Maximilian Ho Yat, Zhang, Ju, Marques, Ana Rita Pinheiro, St-Hilaire, Sophie
• Format: Article
• Language: English
• Subjects: Aquaculture; Harmful algal bloom; Hydrogen peroxide; Pond water
• ISSN: 0044-8486; 1873-5622; 0044-8486
• DOI: 10.1016/j.aquaculture.2023.739932

Microcystis sp. is a harmful cyanobacterial species commonly seen in earthen ponds. The overgrowth of these algae can lead to fluctuations in water parameters, including DO and pH. Also, the microcystins produced by these algae are toxic to aquatic animals. This study applied hydrogen peroxide (7 mg/L) to treat Microcystis sp. in a laboratory setting and in three earthen pond trials. In the lab we observed a 64.7% decline in Microcystis sp. And in our earthen pond field experiments we measured, on average, 43% reductions in Microcystis sp. cell counts within one hour. The treatment was found to eliminate specifically Microcystis sp. and did not reduce the cell count of the other algae species in the pond. A shift of the algae community towards the beneficial algae was also found post-treatment. Lastly, during the pond trials, the gill status of Tilapia and Giant tiger prawn were not affected by the H2O2 treatment suggesting this may be a good mitigation strategy for reducing cyanobacteria in pond aquaculture. •Microcystis sp. blooms are commonly found in earthen aquaculture ponds and can affect fish health and public food safety.•Hydrogen peroxide successfully controlled the cyanobacteria in ponds without affecting beneficial algae and aquatic animals.•Pros and cons of the hydrogen peroxide treatment against harmful algal bloom and how to apply this mitigation.