Jeff Bush, 37, was in his bedroom Thursday night when the sinkhole opened up and trapped him underneath his house, CNN reported.
Rescue workers left the site Friday night, saying the hole is still expanding and the house could collapse at any time.
"Until we know where it's safe to bring the equipment, we really are just handicapped and paralyzed, and can't really do a whole lot more than sit and wait," Hillsborough County Fire Chief Ron Rogers said Friday. "It's a tough situation. It's even tougher for the family."
Bush's brother and roommate Jeremy said when the sinkhole first opened, he tried to rescue his brother, by standing in the hole and digging through the debris with a shovel.
"I couldn't get him out. I tried so hard. I tried everything I could," Jeremy Bush said. "I could swear I heard him calling out."
"Everything was gone. My brother's bed, my brother's dresser, my brother's TV. My brother was gone," he said.
The sinkhole is about 20 feet to 30 feet across and may be 30 feet deep, said Bill Bracken, president of an engineering company assisting emergency workers
"It started in the bedroom, and it has been expanding outward and it's taking the house with it as it opens up," Bracken said.
Although the Florida Department of Environmental Protection said sinkholes are very common in Florida and especially in Hillsborough County, which accounts for about two-thirds of the state's sinkhole-related insurance claims, Mike Merrill, county administrator for Hillsborough County, said the sinkhole that opened up under the Bush home was not "your typical sinkhole."
"They still have not been able to find the boundaries of the underground chasm. For that reason, we're being very deliberate, he said. "We're very frustrated. But we're pursuing it as quickly as we can, as safely as we can."
Jeremy Bush said he just hopes rescuers can find his brother.
"I'm praying that there's an air pocket in there ... but I can't see nobody surviving that long in a hole like that. There was too much dirt, too much stuff," Jeremy Bush said. "He was my brother, man, I loved him."