How to Remove Iron from Water in BioFloc Fish Farming (Aquaculture)
It took me sometime to get to know about “how to remove iron from water” for aquaculture and same here I have described step by step to make you understand. Water preparation plays a very critical role in BioFloc Fish Farming. We need to set the water parameters as per the type of fish or shrimp that you are going to culture. It’s very essential to understand the fish lifestyle and their behaviors to provide a better environment to grow.
Iron is commonly found in water in most of the places in India. Excess iron in water can be harmful to fishes and their growth. Some fishes can tolerate more than 8ppt of iron content in water and some may not tolerate more than 1ppt of iron. There are three types of iron found in water i.e.
- Ferric
- Ferrous
- Bacterial
One cannot identify easily the Ferrous Iron, it’s clear and dissolved in water. Upon oxidization, Ferrous Iron becomes Ferric Iron, which is in solid format and can be easily filtered. 
The Bacterial Iron can be commonly seen in India, it makes the watercolor red and slimy. By looking at the watercolor, you can easily identify.
This type of water is not at all suitable for fish farming. Overall 0.1-0.3ppt iron content in water is perfectly fine for fish farming.
At the time of water preparation, it’s very crucial to understand what type of fish you want to culture and how much iron content in the water they can tolerate. Based on which the required water parameter to be maintained.
Let’s discuss the number of ways How to Remove Iron from Water in Biofloc Fish Farming;
The easily available solution for removing iron from water is the Iron Removal Filter, which is already available in the market and one can easily buy the iron filter. But there are some pros and cons;
- Iron Filter is Costly and everyone cannot afford to buy it
- Iron Filter works very slowly and to filter 10K liter of water it will take more than one week time
- More water wastage
- Periodically maintenance
The cheap, affordable and best solution to remove iron from water is using the Potassium Permanganate (KMNo4) Solution.
Using this technique Iron and Manganese can be removed from the groundwater using oxidation by Potassium Permanganate (KMO4) followed by filtration. It can remove 100% iron from water and all the iron residues will sit at the button of the tank.
How to remove iron from water using Potassium Permanganate (KMN4)
Follow the below steps to remove iron from water using KMNO4 Solution.
Step1: Buy a 20gms Potassium Permanganate packet, which will cost you roughly ₹25
Step2: Take a 25-liter bucket and add 20 grams of Potassium Permanganate into it and stir well
Step3: Now add the Pottasium Permanganate solution into every corner the 10K BioFloc Tank, so that it mix well
Step4: Now keep the aeration for the next 18-24 hours for the oxidation process to take place and stop it. Slowly the Ferric Iron residues will start settling down at the bottom of the tank
Step5: Once the iron residues settle down at the bottom of the tank the water will look clean. Using a water pump, transfer the clean water to the other tank and remove the iron residues from the base.
This is a quick and easy solution for how to remove iron from water in BIOFloc Fish Farming. But the only challenge here is, you may need a water process tank to process the iron water.
I am using this technique of IRON Removal for quite a long time and found it to be a very cheap and easy solution.
Iron Removal Process in a temporary tank outside of my BIOFloc Farm
Please share your thoughts and comments, if you have a better solution than this, let me know.
Important Note:
- After Iron Treatment don’t use the water immediately because the KMNO4 effect will be there, which may kill the bacteria in your Biofloc Tank
- Leave the treated water for at least for 4-5 days and use it
You can watch the below video where I have demonstrated everything step by step to make you understand.