Trainer Tony Vasil denies being involved in the 'Aquanita eight' top-ups conspiracy, arguing other people went behind his back to dope his horses.

Vasil said he did not know about horses being given illegal race day treatments and never administered any top-ups or asked anyone to do it on his behalf.

He repeatedly denied any involvement in the cheating conspiracy at the appeal over his three-year disqualification.

Vasil agreed with Racing Victoria barrister Jeff Gleeson QC that text messages between others suggested he was involved in the top-ups practice.

"You must have been outraged and furious when you learned that you had been dragged unwittingly into this great scandal in which you were utterly innocent," Gleeson said.

Vasil replied: "Absolutely."

Stablehand Greg Nelligan and his wife Denise admitted their roles in the long-running practice of giving horses top-ups of sodium bicarbonate and Tripart paste on race days, after being subpoenaed to appear at the appeal for Vasil and three other trainers.

Vasil accepted Greg Nelligan was involved in topping up his horses on numerous occasions.

"I never knew or never gave consent to any of my horses being treated," he told the Victorian Civil and Administrative Tribunal on Wednesday.

Vasil was referred to in texts about top-ups found on Nelligan's phone after the float driver was caught giving the Robert Smerdon-trained Lovani a top-up on Turnbull Stakes day in October 2017.

Vasil did not send any of the texts.

Gleeson said Vasil was suggesting there was a conspiracy to top up his horses without his knowledge.

"It must be your position that behind your back and unbeknownst to you, Greg Nelligan, Denise Nelligan and your foreman Trent Pennuto are involved in topping up your horses on race days with sodium bicarbonate," Gleeson said.

Vasil replied: "It appears to be."

Gleeson said the texts suggested a number of members of the Aquanita eight were involved in doping Vasil horses, but the trainer still maintained he did not know.

"Please Mr Vasil, stop the lies. You did know," Gleeson said.

Vasil said: "I didn't know."

Vasil, whose disqualification related to seven top-ups between December 2010 and July 2013, said he was stunned that his foreman Pennuto was involved.

Asked about 2013 texts between the Nelligans talking about Vasil doing a "very silly thing" by topping up horses in a truck that was searched by stewards, the trainer said it was a fantasy in their heads.

"It's bizarre."

Eight people associated with thoroughbred management company Aquanita Racing were disqualified over the conspiracy to cheat in more than 100 races over seven years, with Smerdon and the Nelligans disqualified for life.

Four trainers - Smerdon, Vasil, Stuart Webb (four years) and Liam Birchley (one year) - appealed, but Vasil was the only one to testify before VCAT.

Pennuto (two-year disqualification) and stablehand Daniel Garland (one year) denied being involved to the tribunal.

VCAT will hear closing submissions in March.