A day a the Mud Crab Vertical Farm with RAS | Aquaculture Operations

Estimating the profitability of the mud crab farming business requires detailed knowledge of capital cost, operating cost, and revenue. A major component associating to operating cost is labor/manpower cost. However, it can be difficult for those without prior knowledge in crab farming to estimate the amount of manpower/labor cost needed for the project. In this blog post, we will be revealing our typical working day at the farm.

9:00-9:15 am

Our typical day starts off by checking the key water parameter -- ammonia in the farm. This is to ensure that ammonia is at a safe level before introducing feed into the system. If the ammonia level is already high, feeding will result in increased ammonia levels beyond permissible levels. Check out our previous article on ammonia chemistry and removal here.

9:15-11:00 am

If ammonia is within safe values as per standard operating procedures, we will start feeding the crabs. Crabs are nocturnal and will usually consume more feed during night time. Hence, it is important not to overfeed in the morning. Other farm operators will tend to feed their crab mud crab around 6 am. Feeding the crabs earlier is better for the crabs but will depend on whether employees are staying on-site. Note that the feeding rate for the crabs will depend on the size of the crabs, and the type of feed. It is the job of the feeder to understand the requirements and not to overfeed nor under-feed the crabs. The feeder will also take the opportunity to check on the crabs, and to remove any crabs that are dead or ready to be sold. Typically, this task will take around 1.5-2 man-hours for 1000 systems.

11:00-1230 pm

Majority of the work required to be done in the morning is the feeding process. After which, the team might spend time on miscellaneous tasks on the farm. The typical task will include housekeeping, inventory, feed preparation, etc. Depending on the feed that you intend to use, the team might also have to allocate a portion of their time in this task. Typical feed preparation for fresh fish includes defrosting, removing the head and cutting them into standard sizes. Other feed preparation task could also include making a wet based feed from fresh and formulated ingredients. The usage of formulated feed is the most efficient, as no time is needed for the preparation of the feed. The team would also utilize some this time to start packing for any crab orders during for restaurants that operate during lunchtime.

2:00-3:30 pm

The first task to be completed during the afternoon session is to clean out all the uneaten feed in the crab farm. The time spent on this task can vary significantly for different farms depending on the type of system and experience of the team. We will start with performing backwashes on the sand filters, followed by cleaning of individual boxes. Removal of uneaten fish is easier than uneaten formulated feed that tends to disintegrate over time. This task takes 1.5-2 man-hours to perform for 1000 boxes. It is important to note that our system uses a removal stand-off pipe system. Systems that utilize a flush valve to purge out solids are much more efficient in the removal of any uneaten feed (fresh feed or disintegrated formulated feed). Typical pitfalls that many first-time investors will face is selecting a crab box solely based on capital cost, while incurring high operating expenses down the line due to low productivity.

3:30-4:00 pm

After feeding, the team will then proceed with measuring other water parameters in recirculating aquaculture systems. These parameters are not as crucial as ammonia, but still somewhat important to the development of mud crabs. Some of these tests include Calcium, Magnesium, phosphorus level, etc.

4:00-5:00 pm

Depend on the received orders for the day, the team will also start packing for crabs to be sold to restaurants. In Malaysia, customers prefer eating mud crabs during dinner time. Crabs are packed neatly in Styrofoam boxes holding 20kg of crabs per box. Depending on the location of the farm, restaurants operators might have to provide delivery services for the product. Efficiencies in logistics play a big part in the business, as additional headcount might be needed to deliver the crabs. One of the advantages of using recirculating aquaculture systems is being able to station your farm in any location. Being near to the consumers, you will eliminate much of the logistical cost. However, locating your farm near to consumers will often mean higher rental cost due to prime real estate. Nevertheless, each business should outweigh the relative importance of the two variables.


5:00-6:00 pm

The remaining task is to feed the crabs for the night. The portion given here will be bigger than what was provided in the morning. For some farm operators, additional feeding is done around midnight. Consistency in feeding is important in ensuring that mud crabs develop well. This task will take around 1 hour to complete, and the team will wrap up and head home.


Farming crabs is hard work, it takes true commitment and passion to run a crab farm. We would also like to take this chance to thank the operation team at RAS Aquaculture for doing a great job. We hope to inspire and guide many of the farmers all over the world.


#ras #aquaculture #urbanfarming #indoorfarming #mudcrabfarming #crabfarming #sustaianble

8 Kawasan Perindustrian Kluang, 86000 Johor, Malaysia

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