|The five friends died last summer while swimming at Camber Sands|
Lawyer Patrick Roche, who is representing the families, also said in opening remarks that his clients were "keen for lessons to be learned" and that "no-one else suffers the same appalling tragedy".
The five men who died last August were Ken Saththiyanathan, 18, his brother Kobi, 22, and their friends Nitharsan Ravi, 22, Inthushan Sriskantharasa, 23, and Gurushanth Srithavarajah, 27.
The inquest heard Sri Lankan-born A-level student Ken Saththiyanathan was a "healthy young man".
The brothers' father, Arumukam, said in a statement they had "good swimming ability" and his sons swam in Sri Lanka almost every weekend before they came to the UK in July 2008.
He added that his son Kobi loved Camber Sands and had visited three times in 2016 before his death.
Toxicology tests for both brothers were negative for drugs and alcohol.
Consultant forensic pathologist Dr Brett Lockyer recorded a cause of death of immersion (drowning) for both following post-mortems.
Ahead of the inquest, Ajirthan Ravi, the brother of victim Nitharsan Ravi, said he hoped the inquest would lead to an improvement of safety at Camber Sands.
Mr Ravi told reporters: "We are just hoping that it will be more secure and safer and more lifeguards, and that people are more protected."
This year, four lifeguards will patrol Camber Sands Central from 10am to 6pm, seven days a week, until 1 October. A further two lifeguards will patrol Camber Sands West during the same times from 8 July to 10 September.