How to PROPERLY TREAT WATER in RAS for AUSTRALIAN REDCLAW CRAYFISH | Australian crayfish farming

Summary

Anton Belcher, an experienced engineer, discusses the intricacies of water treatment systems for crayfish farms, focusing on Australian Red Claw crayfish. He covers the ideal tank dimensions, mechanical and biological filtration, and the importance of biofilters to reduce water consumption. Anton advises against ozone disinfection due to its negative impact on crayfish growth but recommends UV disinfection for pathogen control. He also touches on heating systems, oxygenation methods, and the necessity of a control panel for monitoring the farm's operations.

Takeaways

• 🚀 The speaker, Anton Belcher, an engineer with over 10 years of experience, discusses water treatment systems for crayfish farms, specifically for Australian Red Claw crayfish.
• 🦐 Shallow trays, typically 20-25 cm deep, are used for crayfish farming, with water temperatures maintained between 26-28 degrees Celsius.
• 🏞️ Trays can be arranged in multiple levels to maximize production yield per square meter of the farm, with dimensions varying from 1x1 meter to 10 meters long and 2-3 meters wide.
• 🌡️ Optimal tank size for grow-out crayfish is 35 meters long and 1.5 meters wide, with smaller tanks used for incubation and broodstock.
• 💧 Water treatment for crayfish involves mechanical treatment to remove suspended solids, followed by biological filtration to process nitrogen compounds released by the crayfish.
• 🚫 Ozone disinfection is not recommended for crayfish farms due to negative impacts on crayfish growth.
• 🌡️ Ultraviolet disinfection is suggested for industrial-scale crayfish farms to ensure the removal of pathogens.
• 🔁 A heat exchanger is recommended for maintaining water temperature, as it is more cost-effective than electric heaters, especially in closed-loop systems.
• 💨 Oxygenation can be managed through fixed bed biofilters with aeration systems, or by using diffusers and compressors, or an exogenator fed by an oxygen concentrator for larger farms.
• 🛠️ For small-scale or household crayfish farms, DIY solutions and local materials can be used, but for industrial-scale operations, industrial technology is recommended for efficiency and reliability.

Q & A

What is Anton Belcher's profession?

Anton Belcher is an engineer with over 10 years of experience in constructing fish farms.

What is the primary topic discussed in the script?

The script primarily discusses water treatment systems at a crayfish farm for growing Australian Red Claw crayfish.

What are the typical dimensions of the trays used for crayfish farming?

The trays used for crayfish farming are usually small and shallow, about 20-25 centimeters deep, with dimensions varying from one meter by one meter to 10 meters long and two or even 3 meters wide.

What is the purpose of the shelters within the crayfish trays?

The shelters within the crayfish trays are made of pieces of sewage barbs connected to each other, forming sections to provide hiding places for the crayfish.

What is the optimal water temperature for crayfish farming?

The optimal water temperature for crayfish farming is between 26-28 degrees Celsius.

How often should the water be exchanged in a crayfish farm?

At a crayfish farm, one water exchange per hour is sufficient due to the low stocking intensity.

What is the role of mechanical water treatment in crayfish farming?

Mechanical water treatment filters out suspended solids, pieces, residues of uneaten feed, and other debris, which is crucial for maintaining water quality in crayfish farms.

Why is a biofilter essential in crayfish farming systems?

A biofilter is essential as it treats nitrogenous waste, which is toxic and needs to be removed from the system. Without a biofilter, daily water consumption would have to be dramatically increased.

What are the two main types of biofilters mentioned for crayfish farming?

The two main types of biofilters mentioned are fixed bed biofilters and fluidized media biofilters.

Why is ultraviolet disinfection recommended over ozone for crayfish farms?

Ozone has been found to stunt the growth of crayfish negatively, unlike in artificial species farming where it works well. Ultraviolet disinfection is recommended as it ensures water treatment of various pathogens without negatively affecting the crayfish.

How should the water temperature be maintained in a crayfish farm?

A heat exchanger is recommended for maintaining the water temperature in a crayfish farm, as it is more cost-effective than using an electric water heater.

What are the options for oxygenation in crayfish farming systems?

Options for oxygenation include doing nothing at all for small farms with low density, aerating the water directly in the trays, or using an oxygenator, especially for industrial-scale farms when natural oxygen is insufficient.