The low interest rates that have prevailed for years benefit real estate developer Donald Trump. As a possible president, he's worried. 

"I've always loved low interest rates as a developer and I've always done well with low interest rates," he said on an interview on  Bloomberg's With All Due Respect, Tuesday on Bloomberg Television. 

"I think you're creating a bubble and the bubble could explode."

Trump praised Paul Volcker, the inflation-taming Fed chairman of the early 1980s, as a role model for the type of central banker he would pick. Volcker, now 87, not only had good ideas but the right style, Trump said. 

"His policy and his demeanor, there was something very solid about it," Trump said. 

Trump, who leads Republican candidates at 21 percent in the latest Bloomberg Politics poll, will face his rivals in the cycle's first debate on Thursday.

In the interview, he criticized the Export-Import Bank as "featherbedding" for politicians, said he favored full transparency of money in politics and claimed to sleep about four hours a night. 

"I have some friends that don't sleep very much," Trump said. "We have more hours in the day to work and compete, so it is a definite advantage."