In May 1899 the Parks Committee received a proposal for creating a fish hatchery and instructed the Borough Engineer to prepare plans and estimates for a building combining a hatchery and aquarium. The Superintendent was authorised to purchase 12 tanks for hatching purposes. The estimate of £250 was accepted by the July Committee meeting and the building was completed by the end of the year.
The hatchery was operational from January 1900. In the first year 12,000 trout ova were laid down, but only 400 survived to be placed in "the pool known as Llandenis' Well" in May. The result in the second year was similar, the problems being traced to contaminated water in the rearing ponds. These were in the Botanic Garden near the aquarium and hatchery, but in November 1901 it was decided that fish rearing ponds would be formed in the Wild Gardens.
After its early difficulties were resolved the hatchery flourished. It produced plentiful young fish to stock the lake, and a regular surplus of both ova and fish which could be sold. The Parks Committee agreed in December 1901 that surplus ova from the hatchery could be sold as only half of the 40,000 produced would be needed. In March 1907 the Parks Superintendent reported that 3,500 yearling trout had been sold. Over 3,000 yearling trout were placed in the brook at the head of the lake in April 1908 to compensate for the depletion of fish expected to take place during that year's fishing season. In the same month a further 22,000 fry, 3 months old, were sold for £19.5s. In April 1909 over 25,000 young fish were placed in shallow parts of the lake, and in the financial year ending March 1909 fish to the value of £70 were sold from the hatchery.
Interest in fishing declined after 1910, as did the quantity of fish in the lake (for reasons described in the section on Fishing). The supply of ova from fish in the lake also reduced, such that the hatchery was no longer able to produce a satisfactory supply of young fish. No serious attempt was made to revive fishing until the early 1920s. Mature trout were purchased to stock the lake in 1922-23, and yearling fish reared in the hatchery in 1921 and 1922 were placed in the lake. Receipts from fishing in 1922 and 1923 were disappointing and no further attempt was made to rear fish in the hatchery.
In the 1938 Inventory of Parks Buildings and Equipment, no special equipment was recorded for the Fish Hatchery and Aquarium: the only items listed were an extension ladder and two chairs. An additional comment, possibly added later, indicated that the Fish Hatchery and Aquarium was "In abeyance. Pending decision by Committee".
Sources of Information
In general, the information in this section is taken from A. A. Pettigrew, The Public Parks and Recreation Grounds of Cardiff, Volume 3.
Other sources are: