Two things decide whether a fish operation runs clean: the water the fish live in, and the water and surfaces the fish touch after harvest. Chlorine dioxide is used on both, and for a reason that matters more here than in almost any other industry. It does the work without leaving something behind on the product.
The problem with chlorine in a fish operation
Chlorine is the default almost everywhere else. In aquaculture it carries two specific problems.
Chlorine and chloramines are toxic to fish. They pass through the gills into the bloodstream and interfere with the ability of red blood cells to carry oxygen. Water that is perfectly safe for people and for terrestrial animals is hazardous to anything that breathes through gills. That is a narrow margin to manage in a production basin.
Chlorine forms byproducts. Reacting with organic matter, it produces trihalomethanes and haloacetic acids. In a system loaded with organic material, which describes every fish operation, that reaction is constant.
Chlorine dioxide oxidizes rather than chlorinates. It does not form THMs or HAAs, it holds its effectiveness across a wider pH range, and it keeps working in the presence of organic load where chlorine gets consumed first.
Where it works on the farm
Water treatment. Chlorine dioxide is used to control microbial contamination in aquaculture water systems and to prevent algal blooms and biofilm from establishing in lines and tanks. Cleaner systems mean better flow and fewer places for organisms to shelter.
Fish production basins. Used continuously at low concentration to maintain microbial water quality. The rate depends entirely on your source water and organic load, which is why testing comes before dosing.
Surface and equipment disinfection. Tanks, filters, lines, nets and handling equipment. This is where biofilm actually lives, and it is the reason a system that tests clean at the intake does not test clean at the outlet. Learn how to remove biofilm in the system.
Where it works in the plant
Process water. Chlorine dioxide is used in place of aqueous chlorine in seafood processing water, for the same byproduct reason it matters upstream.
Food contact surfaces and equipment. Selectrocide® is EPA registered as a disinfectant and sanitizer for food contact surfaces and equipment, with no rinse required at use concentrations. In a plant running cold and wet all day, a no-rinse step is not a small thing.
Shelf life. Published work in the Responsible Seafood Advocate has reported reductions in microbial populations on fish held at 5°C over seven days when chlorine dioxide was used in place of aqueous chlorine. That is third-party research, not our claim, and it is worth reading directly if shelf life is what you are solving for.
What Ultra-Pure means, and why it matters most here
Most chlorine dioxide is made by mixing precursor chemicals on site. That process leaves chlorite and chlorate behind in the finished solution, and whatever is in the solution goes wherever the solution goes.
Selectrocide® is generated inside a sealed micro-reactor. Water vapor passes in. Only chlorine dioxide gas passes out. The reactants and the byproducts stay sealed inside the membrane and get thrown away with the pouch. See How Selectrocide Works.
For a seafood plant, that is the entire argument. You are treating water that touches a product someone eats. What is not in the solution cannot end up on the fillet.
The micro-reactor is covered by patent US 12,036,525.
No generators, no bulk chemistry
This is the practical difference for most operations. There is no generation skid to buy, install, permit and maintain, and no bulk precursor chemicals to store and handle. A sealed pouch goes into water and makes the solution.
For working volumes:
- Selectrocide® 5G makes 2,500 gallons at 0.5 ppm
- Selectrocide® 12G makes 6,000 gallons at 0.5 ppm, or 3,000 gallons at 1 ppm
Getting the rate right
Dosing is not one number, and anyone who gives you one without seeing your water is guessing.
It depends on your source water, the organic load coming in, the size and age of the system, whether you are on fresh or salt, and whether you are clearing out an established biofilm or holding a clean system clean. Those last two are different jobs at different rates.
Two things before you set a rate:
- Test your source water. It drives everything downstream and it is the cheapest information in the process.
- Clear the system first. Heavy sediment and debris will consume product that should be treating water.
Documentation
Every registration, notification and listing we hold is published with the numbers, so your auditor does not have to take anyone's word for it. SMT Regulatory portfolio.
Talk to us about your operation
Tell us whether you are treating production water, process water, or both, what your source looks like, and what volume you are running. We will help build a protocol that fits and quote it.
Request wholesale pricing or contact us at inquiry@selectivemicro.com