Ex-rifleman Gareth Mcallister, from Leeds, was aided by a doctor and an unnamed firefighter from Madrid performed CPR on Blair Scott until paramedics arrived.
The youngster, Blair Scott, was on holiday with dad Kevin and stepmum Ashley Moore when the accident happened at the Magic Robin Hood resort in Benidorm.
The family are now appealing for any footage that could help them understand what happened in the build up to the event.
Blair was left fighting for his life in hospital in Alicante and was initially in a coma but it has now been confirmed he is “awake and talking.”
Sharon and husband William said Gareth was “our hero” on a post in Facebook. William said: “We thank you from the bottom of our hearts sir, you are our hero.”
Sharon added: “Words are just not enough to tell you how thankful we are for what you did for Blair, me and my family – thank you so much.”
The stepmum of Blair, Ashley said: “I was at the pool with Blair, his 13-year-old sister and my one-year-old. I was only gone for a few minutes. When I came back, all hell had broken loose. The lifeguards did nothing.”
Relatives and witnesses have accused the resort of negligence with claims that lifeguards didn’t know how to perform CPR.
It was also claimed that the majority of the guards spent most of the time on mobile phones.
Gareth’s partner, Sarah Garth, wrote on the resort’s social media: “Your lifeguards did nothing and left the care of a young boy in the hands of people who were doing CPR wrongly.
“They told my partner there was no pulse and, within seconds, my partner found one.”
The hotel posted: “We will take new safety measures and strengthen supervision in pool areas. The safety of customers is the most important.”