Thugs poured toilet cleaner into a couple's garden pond in West Yorkshire, killing around 200 fish.
The attack on the pond in Moorhouse Avenue, Darnley has left the owners, Danny and Pam Turton devastated.
They built the pond when they first moved into the house 30 years ago. But on Tuesday morning they discovered the dead fish — and an empty bottle of Harpic toilet cleaner next to the pond.
Danny Turton lost his twin brother David to cancer last year and the pond, which contained goldfish and Koi, had been useful for him in taking his mind off the trauma. He told Wakefield Express: "It was my main hobby and everything I had.
"One of the first things I did when we moved here was to put a pond in the front garden, and we had built up a collection of fish over 30 years. But now it has all gone. It is such a shock.
"It involved a lot of time and effort, cleaning it out and taking care of the fish. They knew me and would come towards me when I approached the pond.
"All the children who passed by the garden would stop and gather round to have a look.
"It must have been done with malice, someone has been determined to do it."
The police have confirmed that the matter is being treated as criminal damage.
Anyone with information about the incident is asked to contact the Wakefield Central NPT on 101 or to call Crimestoppers on 0800 555 111.
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