Twenty years on, Danny Hanley has travelled from Queensland to Bali to remember his daughters.

Simone, 29, and Renae, 31, were visiting the popular holiday destination for a girls' trip when terrorists struck.

"Renae was at the bar, not far from the blast, she never stood a chance," Mr Hanley told AAP on Tuesday.

On Wednesday, he will place a floral bouquet at the ground-zero monument opposite the former Sari Club and Paddy's Bar where the bombs exploded, killing 202 people including 88 Australians.

After being repatriated, Simone battled for life in a Perth intensive care unit, suffering severe burns.

She was under the care of esteemed plastic surgeon Fiona Wood, known for her spray-on skin technology for treating burns victims.

"We said to her (Dr Wood) 'we've already lost one daughter, can you please do whatever you can to save our other daughter?' And that prompted her to think about using our skin," Mr Hanley said.

"It was a heavy burden for Fiona too, she took a keen interest in Simone. She understood our dilemma."

Mr Hanley and his son Daniel Hanley asked to donate skin to save Simone but the procedure was so risky they were advised against it. The medical prognosis was there could be three victims rather than one.

A committed Catholic, Mr Hanley told AAP his faith brought immeasurable comfort.

"I still say prayers for the girls every night without fail and that gives me a certain comfort to know God's looking after them. It's a prayer and a couple of Hail Marys, and I ask God to look after them. It's helped me all these 20 years, and coming here."

Mr Hanley said 2022 marked a milestone.

"I'm happy I'm here for the 20th - it means a lot because after that I think the memorials will peter out significantly.

"It's almost like closure. Twenty years of suffering is enough. You've got to really accept closure with the marking of memorial services. After that you just live with it yourself.''

He has attended all of the Bali commemorations except during COVID-19, sometimes with his son, and represented survivors and families on the 10th anniversary.

"I felt honoured to speak on their behalf."

In 2022 he has travelled alone.

"It's a bit lonely. You think about what could have been and what wasn't, you think of grandchildren - as everyone does. Poor Renae she never married, whereas Simone experienced marriage and being a mother (of then-four-year-old Noah).

"But it's a milestone, it's a big occasion. It's long enough to get some respite from the pain. You never get over it fully."

This may be the last time Mr Hanley visits Bali. His former wife, who had for many years holidayed on Bali, has never returned since their daughters' deaths.

Like the relatives of other victims, news that Bali bomber Umar Patek was set to be released on the 20th anniversary added salt to an open wound.

There's also disappointment that a peace park proposed for the bomb site has not gone ahead.

"A lot of people were looking forward to it being open for the memorial," Mr Hanley said. "It would have been the perfect time."

Mr Hanley will lay another bouquet for his daughters in Bali on Wednesday at the Australian Consulate-General's memorial service, to be attended by hundreds of people.

"It feels good, for the girls to be given recognition. When you lose loved ones, you want them to be recognised as much as possible. I like them to be put up in lights."

A number of services are being held across Australia, including in Canberra where federal politicians will gather, and at Coogee where six members of the local Dolphins footy club were lost to the Bali bombings.

Australian Associated Press