What size fish feed pellets are more appropriate to feed the fish？

2021-03-20 Back to List

The number of fish feed pellets that an individual fish can catch is related to its swimming activity, which is, in turn, partially temperature-dependent. 

Rainbow trout could catch larger numbers of pellets in a single feed portion as temperatures increased from 5 to 15°C under laboratory conditions; this change is likely mediated by changes in the fish’s activity at different temperatures. The feeding rate of brown trout increased rapidly between 3.8 and 6.8°C, remaining relatively stable between 6.8 and 19.3°C, before decreasing at temperatures above 19.3°C. Changes in the feeding and swimming activity of salmonids at different temperatures have been presented by others with the greatest change in activity occurring between 5 and 10°C. In aquaculture, the feed delivery rate should therefore be taken into account when calculating a feeding regime.

The size of feed pellets and the rate at which they are delivered may affect the amount of feed an individual fish can ingest over a period of time. Pellets of sub-optimal size or pellets that are delivered at a high rate may cause wastage, as fish may be unable to catch large numbers of pellets before they sink through the net pen. Salmon farmers use many different sizes of feed pellets during the grow-out period, and each time the size is changed, new calculations for the optimal number of pellets per fish and delivery must be done. It would therefore save both time and money if fewer sizes of pelleted feed can be used for larger parts of the grow-out period.

At some extreme, pellet size will obviously have an effect on fish performance, and there are indications of this effect presented here. For example, a pellet that is larger than the gap width of the fish or is so large that handling time becomes a limiting factor in the fish's ability to ingest enough pellets to maintain good growth will clearly have adverse effects. Adult salmon showed a more immediate response to larger pellets but that these were more likely to be rejected than pellets of a shorter length.

Pellets slightly smaller than the "normal" commercial size were eaten at the fastest rate, thereby indicating that the salmon are perhaps adjusting their feeding behavior to compensate for a smaller feed pellet size. For Arctic charr reared under hatchery conditions, the optimal pellet size has been suggested to be around 2% of the fish's length. Others have suggested that for a range of fish species, the optimal feed size appears to be 25–50% of the mouth width. It appears that fish can adjust to reasonable deviations from the optimal pellet size with no significant negative effects on growth.

Hope this article can help you know more about fish feed pellets, if you want to build your own fish feed making plant, please contact Richi Machinery.The following are some of our fish feed equipment recommendations:

1.Fish feed grinding machine

Fish feed grinding hammer mill machine is a special equipment to break large materials into fine powder.  Raw materials in feed crusher are crushed into suitable particle sizes for feed mixer procession. Final size of materials can be controlled by inserting a screen with different sized holes. With competitive price, simple structure and high efficiency, animal feed crushing machine is mainly employed in the farm, middle sized feeding factory or for family use(such as fish feed pellet production line). is main machine in fish feed production line.

2.Fish feed mixing machine

Fish Feed mixer also called ribbon blender can be divided into ribbon mixer,horizontal feed mixer or single/double shaft mixer used for mixing powdery feed materials in order to ensure the quality and effect of compound feed, installed in fish feed production line.

Fish Feed mixer is a well-working feed mixer for fish feed production line and other livestock feed production plants,horizontal ribbon mixer for you to mix poultry and livestock feed, as well as fish feed, which can mix the raw materials evenly. Feed mixing machine is widely used in animal feed plant and fish feed pellet plant. And the Wet Type Fish Feed Puffing Machine is the high capacity used in feed production line.

3.Fish feed pelletizing machine for fish feed production

Fish Feed Pellet Making Machine also called fish feed pellet mill or Aquatic Feed Pelletizer is widely used for making feedstuff for all kinds of fish, install fish feed production line. And this feed pellet mill can produce different size from 2mm to 20mm and fit for different fishes.

4.Fish feed dying machine

Dry fish feed machinery also called Pellet extruding drying machine or fish feed pellet dryer is used to dry the dish pellets, which can ensure the fish feed pellets quality and benefit the storage of fish feed.

5.Fish feed cooling machine

Fish Feed Pellet Cooler for Fish feed production line which is auto complete feed production line is one of important part, which adopts counter flow cooling theory, and pellets can be cooled completely and evenly through the machine, which is good for the pellet packing and storage.