The owners of Alderneuk Fishery in Terregles are looking to build a new house, cafe, shop, and motorhome hook-up points on the site.
They also intend creating a fish hatchery with hatchery building, tanks and a pond, an accessible fishing platform, and the installation of a sewerage treatment plant.
The family-run business, which has been operating since 2008, has submitted a planning application to Dumfries and Galloway Council which will be determined on Wednesday.
A report on the issue reads: “It is advised that the existing business makes very modest profits, enough to provide a modest wage but with little surplus for further investment.
“The applicants wish to safeguard, develop and diversify the business. By investing in new and improved facilities, they hope to increase income and reduce costs over time, to improve profitability and make the business more financially resilient.”
However, council planners are recommending it is refused, arguing that the proposed siting of the house, office, store, and motorhome hook-up points go against the region’s local development plan.
Concerns have also been raised about potential flooding.
The final decision will be made by councillors this week.