Thirty feet below the surface Johnson showed Cobiella row after row of coral alive and growing after decades of being battered by disease and warmer water.
All of it was planted here by scientists and each fragment started out as only a couple of inches tall.
It all started in Ken Niedemeyer's backyard in the Florida Keys. His daughter needed a 4-H project so they decided to try growing coral.
"Good thing I never read about it because everyone said it couldn't be done," Neidermeyer said.
Their technique worked. They took it to researchers and nine years later it has blossomed to this - the largest man-made nursery project with 5,000 coral colonies growing underwater from Fort Lauderdale to the Virgin Islands. Scientist clip and plant new coral just like pruning a tree, and anchor it with underwater glue. When the coral is big enough, it's moved to a reef to replace dead or dying coral.
"It's just amazing what happens," Neidermeyer said. "A lot more habitat for fish, for juvenile fish, for large fish, for invertebrates."
But they're now facing a new threat - BP oil. Every day, Johnson anxiously checks the forecast for the Gulf "loop current," the system that seasonally carries water, and anything in the water, eastward through the Florida Keys.
"It's definitely devastating to watch what's happening in the gulf and know that it could come here," Johnson said. "I think we are all worried about what's going to happen in this project."
There's little they can do to protect the nurseries. If the oil is weathered and weakened enough, Johnson thinks the young coral just might pull through.
"Those are our little babies, you know," Johnson said. "We put those guys out there. And it's nice to come back in a month or two and see them actually growing. And feel like, 'Wow, I did that. You know, I'm helping. I'm doing something good.'"
With oil coming a little closer every day, she's hopeful at least some of that "good" will survive.
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