Alex, 22, of Park Road, entered the sea near the Metropole Hotel on Princess Parade at around 4.20am on Friday - despite being unable to swim himself.
A major rescue operation involving coastguard teams from Fleetwood and Lytham, RNLI volunteers from Blackpool and Fleetwood, and a rescue helicopter was launched, but tragically Alex lost his life.
Curtis Busby, who worked with Alex at C Fresh fish and chip shop on Foxhall Road and went out with him the night before he died, said: "He was so down to earth and caring. He loved animals and even went vegan because he didn't like the ways animals were treated in factories.
"He was always there for everybody. If ever I needed a roof over my head or food in my belly he was always the first to help out, and he'd never expect anything back.
"The day we found out, we closed the chippy and we all went out. Everyone's emotions are running high. People are tearful. We're all trying to not think about it. We want to remember him for who he was and not how he died. But it has shattered everyone.
"He was always smiling. Whever I came into work he was always the first I'd hear laughing about something.
"The last thing he did was try to help somebody else. That was just who he was."
C Fresh closed on Friday while staff mourned. A spokesman for the restaurant said: "I’d just like to add Alex was truly an amazing young man. All his friends would agree that he was intelligent, hardworking, pleasant, caring, and literally wouldn’t hurt a fly.
"He is a true hero, drowned sacrificing his life to help another.
"He was loved by all his work colleagues, and we miss him terribly. Tragically taken at 22.
"My heart goes out to all his family."
Flowers, buckets and balloons have been placed on the seafront in Alex's memory. An online fundraiser for his funeral has already brought in more than £3,700.His friend Hamish Howitt said he was "a true hero" who was "a beautiful, caring, loving, son, brother and friend to all who knew him."
Unity Academy head teacher Stephen Careless said: "Everyone at Unity is incredibly saddened to hear of the death of former student Alex Gibson. The actions Alex took were truly representative of his character, always thinking of others before himself."
Others took to social media to pay their respects.
Iris French said: "What a tragedy especially to such a caring man. My thoughts are with his family and friends as they try to come to terms with their loss. RIP to a very brave young man."
Julie Sherdley-Davies said: "My heartfelt condolences to his loved ones. He sounds such a caring person and to try to save someone else with no thoughts to his own safety is very heroic."
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