Lerøy Hydrotech Halsa has set out small copies of the measurement frame in smolt tanks with higher fish density than in sea cages. At the smolt supplier Aakvik Settefisk AS they set out two to three small replica frames (40 x 40 cm) in each tank, and the fish needed only , approximately two days to get accustomed to the small frames.
”We left the frames in the tanks for a few months, until the fish was due to be put into the sea” Kurt explains.
This exposed the fish more to the equipment, and thereby making the fish more accustomed. These small copy-frames are easy to set out, and easy to clean [not much fouling in tanks].
The purpose of  the small replica frames being set out in the smolt tanks at Aakvik Settefisk AS Halsa, was to find a more effective adaptation method.
Previously, we only used copy frames in the sea in 1:1 size ratio, and it took quite a long time before the fish were accustomed to the equipment.
But now we can do biomass measurements in our 100 and 120 m rings shortly after we put he smolt at sea, and have good biomass control throughout the production period in the sea.
- It's easy and time saving to have the fish delivered that are already accustomed to the equipment before we put it in the sea, says Kurt Rønning.
They have compared this fish with not accustomed fish on the same site.
A comparison is made only 1.5 months after the smolt is put into the sea, with low density in the cage <5.10 kg / m³ shows:
•  5 cages with fish accustomed during the fry phase in tanks, before put into sea:
Led to many and good measurements, from 500 to 1500 approved fish for 2-3 days. With a underwater camera we saw that the salmon were not afraid of the frame, and swam straight through without any stress.
•  1 cage where the fish were not accustomed before put into sea:
Two to three days gave only appr. 100 approved fish through the frame.
Observations with underwater camera revealed that most of the fish passed the frame on the outside, even when positioned in high density shoals.
- This works very well, and we will continue to do this, "says Kurt. I think it’s very motivating for all our users of the equipment.

General Manager Brit Tørud by Aakvik Hatchery:
It is only positive to be able to help make it easier to achieve better weight control on farmed fish.
As a veterinarian, I am concerned that farmers know the average weight of his fish and has a good overview of biomass on the site.
I have not seen any "negative effects" by placing small copy-frames in smolt tanks.