Hydrogen peroxide used in shrimp culture: Believe and Fact
By Dr. Wiphada Mitbumrung, Ph.D. Applied Marine Biosciences — Wed Jun 10 2026
Hydrogen peroxide (H₂O₂) is widely used in aquaculture as a rapid-response treatment for improving water quality and controlling microbial load. In shrimp farming, it is commonly applied with the expectation that it increases ORP and disinfects the water. These beliefs have led to frequent and sometimes routine use, particularly during periods of water deterioration or disease risk. However, while hydrogen peroxide does have strong oxidative properties, its actual behavior in pond systems is often misunderstood. The gap between perception and reality lies in its chemistry, reactivity, and persistence in aquatic environments.
The primary belief surrounding hydrogen peroxide is that it serves as a stable oxidizing agent capable of improving ORP and disinfecting pond water over a sustained period. This assumption is based on its well-known ability to release reactive oxygen species (ROS), which can damage cellular components of microorganisms, including lipids, proteins, and DNA. In controlled environments, such as laboratory systems or hatcheries, hydrogen peroxide can effectively reduce microbial loads and oxidize organic matter. However, in open pond systems, the situation is far more complex. Chemically, hydrogen peroxide is an inherently unstable compound. Once introduced into pond water, it begins to decompose rapidly, the fundamental reaction is its breakdown into water and oxygen:
2H₂O₂ → 2H₂O + O₂.
This decomposition is accelerated by several factors commonly present in shrimp ponds, including sunlight (UV radiation), elevated temperatures, transition metals such as iron and copper, and high levels of organic matter. As a result, hydrogen peroxide typically has a very short half-life in pond environments, often ranging from minutes to a few hours, depending on conditions. This rapid decomposition has important implications for its effectiveness. While hydrogen peroxide may cause a temporary spike in dissolved oxygen due to oxygen release, this effect is short-lived and does not represent true aeration or sustained oxygenation. More importantly, the increase in ORP is transient. ORP is a measure of the overall oxidative capacity of the system, not just the presence of a single oxidant. Once hydrogen peroxide decomposes, its contribution to ORP disappears, and the system returns to its previous state unless the underlying conditions have been altered.
Another commonly held belief is that hydrogen peroxide acts as an effective disinfectant in pond water. While it is true that hydrogen peroxide can inactivate a range of microorganisms under controlled conditions, its effectiveness in ponds is significantly reduced by its rapid consumption. In natural waters, hydrogen peroxide reacts non-selectively with organic compounds, suspended solids and reduced chemical species such as ammonia, sulfides, and ferrous ions. These reactions consume the oxidizing capacity of hydrogen peroxide before it can exert meaningful antimicrobial effects. Consequently, the actual disinfection impact in pond systems is often limited and inconsistent. Furthermore, the non-selective nature of hydrogen peroxide means that it does not distinguish between harmful and beneficial microorganisms. In shrimp ponds, where microbial communities play a crucial role in nutrient cycling and system stability, this can be problematic. The oxidation of beneficial bacteria, including nitrifiers and heterotrophs, can disrupt the nitrogen cycle and slow the breakdown of organic matter. This may lead to secondary effects such as ammonia or nitrite accumulation after treatment, particularly in systems that rely heavily on microbial processes, such as biofloc systems. The interaction between hydrogen peroxide and organic matter also deserves attention. In ponds with high organic loads, a significant portion of hydrogen peroxide is rapidly consumed through oxidation reactions. While this may provide some degree of organic matter reduction, the process is inefficient and incomplete. Therefore, hydrogen peroxide does not effectively clean the pond but rather temporarily alters the chemical composition of organic matter.
In addition to its chemical limitations, the biological impact of hydrogen peroxide on shrimp must be considered. Although it is generally regarded as safer than some other oxidizing agents, hydrogen peroxide can still cause stress at elevated concentrations. It can damage gill tissues, interfere with respiration, and induce oxidative stress at the cellular level. The sensitivity of shrimp to hydrogen peroxide varies depending on species, size, and environmental conditions, but repeated or excessive use can compromise health and reduce resilience to disease.
One of the most important misconceptions is the idea that hydrogen peroxide can solve systemic pond problems. In reality, its effects are short-term and superficial. It may temporarily improve water clarity, reduce visible organic matter, or create a brief increase in oxygen levels, giving the impression of improved conditions. However, these changes do not address the root causes of water quality deterioration, such as excessive nutrient input, imbalanced microbial communities, and accumulation of organic waste. Without correcting these underlying factors, the system will quickly revert to its previous state.