Pensioner, 76, who killed his neighbour's Koi Carp fish with oil and detergent reveals moment he 'snapped'

A pensioner who admitted to killing his neighbour's fish by sloshing oil and detergent into his pond has revealed the moment his 'patience just snapped'. Irishman Gerry Duffy, 76, was 'driven completely insane' by the electric pump his neighbour used for his pond, which contained several Koi carp. The pensioner and his neighbour Andreas Ptohides were embroiled in a bitter row over the pump's noise, which would lead to the death of around 'five to six' fish. Earlier this month, Mr Duffy confessed to killing the fish by sloshing the pond with motor oil and detergent 'out of sheer frustration and lack of sleep'. The former builder had initially thrown motor oil into Mr Ptohides' pond on March 20, 2026, and matters only escalated. Four days later, Mr Duffy was captured on CCTV climbing into his neighbour's garden on Hadley Road in Barnet, where he damaged the water pipes and electric pump. He then threw detergent, which he claims was 'fairy liquid', into the body of water, and eventually around 'five to six' Koi Carp died. The pensioner, who suffers from Chronic Obstructive Pulmonary Disease, maintains his 'revenge' has since backfired as he claims the pond is 'louder than before'. Gerry Duffy (pictured outside Willesden Magistrates Court on August 4) admitted using motor oil and detergent to kill his neighbour's fish In an interview with the Daily Mail, Mr Duffy said his patience 'just snapped' after several sleepless nights, which he claims was caused by the pond's noise 'He made it worse rather than fixing it,' Mr Duffy claimed, adding that more 'bubbly stuff' and 'tubes' had been put in place. The 76-year-old explained he once had a 'friendly' relationship with his neighbour and even visited their house on one occasion. However, their cordial co-existence on the sleepy north London street was quickly soured when Mr Duffy was 'driven insane' by the noise from the pond. He said the noise from the electrical pump was impossible to ignore after he was left bedridden by a chest infection for an entire week. 'I was just sweating to death,' he said, elaborating as to why he had to have his window open. The pensioner said he now pulls his window 'as tight as [he can]' before taping it with insulation tape, and sleeps on his good ear in a bid to keep out the noise. He also purchased an air conditioner in a bid to keep his room cool but cannot 'stand the noise' because it is 'so loud'. Meanwhile, he and his neighbour had discussed the matter several times, to which Mr Ptohides said he would stop the pump, the magistrates' court previously heard.However, the neighbour later said he would no longer do so because it was ‘not good for the fish’.The pensioner's patience eventually 'snapped' after confronting Mr Ptohides in the early hours on one fateful morning. At around 2am, Mr Duffy says he knocked on his neighbour's door and became 'angry with him' because he was 'not doing anything'. He says Mr Ptohides suggested he 'buy some earplugs' as they only heard the noise from the back, not the front of the property. 'My patience just snapped. I was losing weight, and I was up all night and just walking around in circles,' he said.'I even tried to move into the kitchen, but it's too small to sleep in. I just had no choice.'Mr Duffy contacted the council, whose worker visited and said there was no noise, advising ‘he either move[d] or close his windows’.'I'm paying the price all the time,' he said. 'In the mad panic, it got very aggressive with this noise all the time, so I thought I'd take revenge on them. 'When you're lying here at night time, and you can't have the window open, you're sweating, and you can't sleep.'You feel like you have to do something now, not next week or the week after, and not in a month. He added: 'I just took it, and I popped over his fence and at first I threw things into his pond. I tried some Fairy Liquid just to quieten the noise down.'But everything I did did not work.'He continued: 'He took the foam off and had a backup running, no problem the next night. There was no end to it.'He was out wearing me - it was like a game with him, I think.'The pensioner said he was eventually pushed to the point where he purchased a pair of pliers and 'snapped the electric supply to the pumps'. '[I] cut all the pipes so you wouldn't have it running the next night. I just had to put an end to it.'Now he has it all running again,' he said. 'It's just backfired on me now. The pump is on at the moment.'At the court hearing, the pensioner's COPD, several health issues including type 1 diabetes, skin cancer, and high blood pressure were mitigating factors.It was also heard that his health had declined both physically and mentally in the last year, and that he suffered from ‘severe’ anxiety and depression.Mr Stern, defending, also added that Duffy’s break-up with a partner had also had an impact on him over the last three years. Mr Duffy (pictured) was ordered to pay £565 in compensation, £440 for the pond and associated equipment as well as £125 for the destruction of the fishNow, Mr Duffy worries that he has 'lost his good reputation' among his community in Ireland as well as his family - more importantly, his grandchildren. 'I advise them not to get into trouble, don't smoke drugs and all this. They're getting to that age now,' he said. 'And I try to keep a good, a good, like just show them the good side of life. I don't want them to think, you know, anything less of me.'Meanwhile, his son wants him to move away from the street; however, Mr Duffy does not want to be further away from his grandchildren or his allotment of eight years.The 76-year-old pleaded guilty to three counts of damaging property and one count of unlawfully destroying fish on August 4 at Willesden magistrates' court.Mr Duffy was ordered to pay £565 in compensation, £440 for the pond and associated equipment as well as £125 for the destruction of the fish.He was also handed a two-year conditional discharge order.