After sharing the lead with Gin Twist, Jadzia weakened to finish fifth, eight lengths from the winner.
Melham entered Saturday's race confident Satono Glow could upset her more fancied rivals because of her liking for soft ground which was shown in her debut win at Warwick Farm on March 11.
"I was confident but with fillies down the straight for the first time, you don't want to leave it too late because they can promise the world and then get lost," Melham said.
"Credit to the team educating this little filly. She was a bombproof ride today and I feel that the Sydney horses normally go well in the wet as they are used to being trained on the softer tracks up there.
"She loved the wet today and the way she got through it, this horse was a very easy ride in the end.
"Her attitude really impressed me. She's a small horse to the eye but the feel she gave me, she felt like she had a really big stride underneath her and she settled like she will get further in time."