Hatchery technicians and staff all come with different backgrounds, abilities, and levels of expertise. Due to the size and variety of the industry, there are often candidates hired that have zero experience in fish husbandry.
Perhaps the first goal of every hatchery technician should be to establish what is normal and to identify problems.
At Scotian, we have a technical team with extensive skills, but given the 24/7/365 nature of the operation, we have to train all staff to identify and point out potential issues and problems.
Routine checks are a critical component of the operation. The number of variables affecting the health and safety of the fish are numerous. Even the most technologically advanced control or alarm system requires oversight, inputs, and responses, by hatchery staff.
At Scotian Halibut, we have long-established rounds incorporating checklists for chores (such as backwashing filters) and measurements (such as oxygen levels in culture tanks) that are done a minimum of four times daily. With over 70 motors running 24/7/365, the daily rounds are often our first line of defense against equipment failures and associated complications. These rounds provide monitoring and the checks that often lend warning of imminent and/or present issues that need further attention.
There are five categories presented here that the most common daily checks may fall into. Every facility is going to have its own unique procedures.
SOUND
What does a hatchery sound like? It is remarkable how well one can pick up the pitch and rhythm of each area of a farm. From one day to the next, a change in the sounds and pitch in a room full of pumps and/or water flowing and splashing can have meaning for the hatchery technician.
In the pump room of Scotian’s hatchery, there are 13 pumps running 24/7 and several that operate intermittently. Some are on variable speed drives and the change in pitch from a minute valve adjustment in the next room is clearly audible. A bearing in need of grease or service, a small piece of seaweed or mussels in the pump impeller, a change in flow rate or water level; all of these may be audible at certain points of the system and ring out to the hatchery technician’s ear their own unique call for attention.
WATER LEVEL AND FLOW
An easy visual check of culture tanks and head tanks is water level and flow. There are three water related items to consider on any tank water in, water out, and water level. If all the first two are occurring and the water level is steady at the appropriate level, all is likely well. The important thing to remember is that all three have to be checked. Similarly, it should be verified that pumps are actually delivering the water flow needed.
PUMPS
A hatchery’s pumps are at the heart of its water systems. A pump converts energy to pressure in fluids. Coupled with the piping systems, the pump moves water through the hatchery’s water treatment equipment, to the culture tanks. Pump failure is something that happens often enough that it is often planned for with redundancy in place (a back up pump ready to go on the shelf or installed).
Daily checks for pumps start with (as mentioned previously) verifying that the pump is delivering the water flow as needed. If pressure gauges are in place on the system, these provide a quick and simple check point. Other parameters to check are balance, heat, and sound. Sound was covered above. Balance and heat can be checked by touching the pump and/or motor with the back of the hand. Anything electrical should be first touched with the back of the hand as electricity causes the muscles to contract and therefore would move your hand away from any danger.
A vibrating pump is an out of balance pump. Assuming it was previously in balance, the vibrations could indicate a foreign item has been sucked into the pump and is lodged in the impeller, the pump is cavitating, the pump has been cavitating and has worn itself out of balance, the pump has worn bearings, or the flow is out of the pump’s design range. Any of these symptoms should be investigated further as a vibrating pump is a symptom of problems that will cause further problems to itself or other equipment.
As a rule of thumb, if you can hold your hand to a pump motor for 10 seconds, it is not too hot. Any less and there may be cause for concern. A lack of grease in the bearings, for example, could cause a pump to overheat. A fan that is worn, broken, or plugged with salt could also lead to an overheated motor.
The immediate area around a pump should be inspected for water leakage. Pumps may leak through their seal and be fine. Alternatively, a leak through the seal could damage the motor – either by shorting it out or causing the bearings to wear out prematurely.
TANK AURA
Anything involving many living things gives off an aura that we as empathetic beings can almost instantly pick up on. One of the best examples is the common term of “home field advantage” in sports. Most players and teams perform better at home because of the sense of encouragement from often tens of thousands of cheering fans. A player or team takes the same skills with them wherever they go. Why then, do most have better records at home than away? It is the innate empathetic ability we have to pick up on the feelings of other beings. Next time you look at a tank of fish, ask yourself, “how do they feel”? Hungry, sated, comfortable or not, healthy or not, all these things may be observed by the hatchery technician throughout the day simply by looking at the collective aura of fish in the tank.
Halibut for example, will not move if oxygen or temperature is low; but, they also lie still when sated. They swim when hungry; but, they also swim when irritated (by dirty water for example). So, writing a manual for what behavior means x,y, or z, would create a lengthy in-depth volume not easily learned. The hatchery technician, however, can regularly take note of a tank’s aura and soon learn to pick up on the state of the fish enough to know when an issue may be present.
OXYGEN AND TEMPERATURE
Worth mentioning, oxygen and temperature are the two water quality parameters of most significance during hatchery rounds and daily checks. In any intensive culture environment, oxygen is the first thing that needs supplementation. And temperature changes can have a dramatic effect on water parameters and fish needs. For this reason, these are often the parameters that are alarmed for earliest detection (along with water levels perhaps).
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