Stock improvement means, in the traditional sense, releasing fish.
Holstebro og Omegns Fiskeriforening has for many years had the task of stocking fish into the Storå system.
Whitefish, trout and salmon have been stocked.

Whitefish were stocked as larvae.
Trout were stocked as fry, ½-year-old, 1-year-old and smolt.
Salmon were stocked as ½-year and 1-year-old fish.

Whitefish, trout and salmon were delivered from Frøjk Fiskepark.
In recent years, all salmon was delivered from Denmark's Center for Wild Salmon, Randers.

Stockiong have taken place in accordance with stocking plans drawn up by DTU Aqua.
The plan describes which fish species are to be stocked at given positions. It also appears which size groups are involved, and finally the number of released fish is given.
The plan is created on the basis of a large population analysis in the water system, which is carried out with approx. 6 year gap.

The launch of whitefisk was discontinued as the yield did not match the effort.
In addition, the number of mother fish in Storå fell drastically from many thousands to quite a few fish.

With new knowledge about salmon genetics, salmon mother fish were transferred from Storå to the salmon hatchery at Brusgaard near Randers, which was in charge of hatching and rearing until release time.

Trout production was continued at Frøjk Fiskepark and later transferred to Tvis Mølle Fishfarm after the hatchery at Frøjk Fiskepark closed down.
The production of trout at Tvis Mølle Fishfarm was, in terms of aquaculture, quite small, and although the aquaculture could hardly be traced in the stream, there were costly requirements for new equipment. This meant that it was decided to close the fish farm.
In this connection, the trout situation was analysed. Despite many years of systematic stocking of quality fish, progress in the trout population could not be traced. It even appeared that the population was steadily declining.
On that basis, it was decided to stop the stocking of trout.
The last stockin of trout was a smolt release in 2014.

For salmon, the story is otherwise positive.
In a relatively few years, we have succeeded in building up a strong population of spawning fish.
The stocking figures were adjusted downwards, and the stocking of ½-year-old salmon stopped.
The stock of salmon was still good, and DTU Aqua therefore decided that Storå, as the first watercourse in Denmark, should stop stocking salmon, as the expectation is that the stock is so robust that it is selfsufficient.
In 2017, the last 1-year-old salmon were released in Storå, and the Storå system is thus completely free from releases of all species.

Stock remediation has by no means been discontinued.
It is now targeted at watercourse restorations and the laying of spawning gravel, where a very large and fruitful work is carried out.
See more about this in the article on spawning areas.

Happily, the results of laying spawning gravel are very fine, so large quantities of fry are produced.
The research shows that the offspring of wild fish, which hatch and grow up in the stream, have a much better survival rate than released fish.