Chalk Stream Trout Farm sustainably farming Rainbow Trout for SEATOPIA

Seatopia Sustainable Seafood Collective has chosen to partner with Chalk Stream Trout Farm in Hampshire England as they raise some of the finest rainbow trout in the world. The quality of the fish produced is directly related to the quality of the water and the high flow rates of the farms. It is the pure chalkstream water that gives the fish a unique fresh, clean taste. The high flow design of the farms produces an exceptionally lean, athletic fish. Slow-grown over two years in the same conditions as a wild trout from the Test and Itchen, they are firm, well-muscled fish.

ChalkStream has worked closely with their feed supplier over many years to develop a specially formulated, high-quality micro-balanced diet. Marine content has been reduced by 60% in the last 10 years, and is sourced from sustainable fisheries certified to IFFO RS. The feed conversion rate (FCR) is between 1.2 – 1.3, and the fish-in-fish-out ratio (FIFO) that is less than 1.

A true rainbow trout raised exclusively in fresh water, ChalkStream fish are red-fleshed and are harvested at the robust and versatile size of 2.5-3 kg.

True chalkstream rivers are fed exclusively by springs emerging from chalk downland. Rainfall filters through the chalk bedrock to emerge gin-clear and full of minerals and nutrients, creating an exceptionally verdant and unique habitat.

The farms are built on the sites of old water mills, providing a huge volume of water (about 36 million gallons per day) for the fish to grow in a constant current that mirrors their natural river environment. Trout grow out in hard-sided and gravel-bottomed tanks and raceways and are kept at a stocking density of 35-40 kg fish per cubic meter of water.

The outflow from the farms pass through specially designed settling channels to remove waste and ensure the water returns to the river in class-A rated condition. The Test and Itchen Rivers are two of the most highly monitored rivers in the UK, and the farm outflows are subject to constant testing by the Environment Agency to ensure water quality.