It was announced on Tuesday that Darius had been found dead in Minnesota on August 11 - the cause of death is unknown.
The Glasgow singer and actor shot to fame in the early noughties after finishing third on Pop Idol in 2002.
He had a number one hit single and his debut album, Dive In, reached the top 10.
Darius went on to have a successful career in the West End, appearing in Guys and Dolls and Chicago.
Among those who paid tribute to Darius was Guardian political editor, Pippa Crerar, who went to school with the singer.
She posted: “So sad to hear about Darius Danesh. We were at school together in Glasgow where the lovely boy was already a star in the making.
“Met up with him again a few years ago on the West End. His warmth, impish humour and energy were constants. Love to his family.”
Radio presenter James O’Brien described him as ‘gentle’, posting: “Darius was a lovely bloke. I got to know him quite well twenty-odd years ago.
“He came across as very confident and ambitious on TV but away from the cameras he was gentle, generous, humble & utterly devoted to his little brothers. What a sad, sad day for them and their family.”
Numerous fans took to social media to share their stories of meeting Darius, describing him as ‘kind’ and ‘decent’.
Charities also paid tribute to Darius for his work helping them.
Cancer Research UK in Scotland posted: “Darius Campbell Danesh had supported Cancer Research UK on a number of occasions, including in 2017 when he sang at our Christmas carol concert at Glasgow Cathedral. We are deeply saddened to hear of his death and our thoughts are with his family and friends.”