The Magheralin man swam the first heat with a time of 15:07.69, a time nine seconds greater than his previous record in the event – 15:07.90
However, his time is not enough to progress to the final and he finished 20th overall.
All four heats are now completed with the eight fastest swimmers progressing to the final.
The 20-year-old had previously broken the Irish senior record in his Men’s 800m Freestyle heat but also did not progress in that event.
The Irishman clocked in a time of 7:51.65 to win his heat and break the first of two Irish senior records.
The Loughborough University swimmer ends his first Olympics with two Irish senior records from just two swims and has an impressive future ahead of him.
Speaking to RTÉ after his race on Friday morning, Daniel Wiffen said: “Over the moon with that race. I would have liked to have been a bit faster but we can’t ask for much more than a PB and [I’m] happy to improve my record by just under 10 seconds as well. It’s great.”
Wiffen puts his improvements down to a lot of hard work and his move to Loughborough.
Fellow Team Ireland athlete Danielle Hill also competed in her second event of the Tokyo 2020 Olympic Games this morning.
The Larne swimmer finished sixth in her Women’s 50m Freestyle heat with a time of 25.70.
Hill was disappointed with her performance on Friday morning and looked downbeat in her post-race interview with RTÉ.
The Olympian said that she felt the need to breathe after 35m, which is not always a good sign.
“[The Olympic experience has] been nice,” Hill said.
“I’ve been so caught up in the emotions of swimming and what happened beforehand that I don’t think I fully enjoyed the experience, but then again it hasn’t been a full Olympic experience.”
Both swimmers will now look towards Paris 2024 after their time in Tokyo.