Aquatics Maintenance Company Fulfills Dream  When John M. Wilson Jr. was a child, he would take his Tonka trucks out to his back yard, dig holes and fill them with water - making his own private ponds. Wilson still likes working with dirt and water. Only now he gets paid for it. "It's weird," says Wilson, owner of Aqua doc, an aquatics maintenance and supplies company. "It's almost like it was meant to be." The company specializes in controlling weeds and algae in man-made or natural ponds and lakes. It serves customers large and small from Columbus to Sandusky to Erie, Pa., but has concentrated until recently around Chagrin Falls, Hudson and Streetsboro. "Lake County is my target area this year," he said. Wilson bought the company from Cloonan and Sons Land and Pond Maintenance in 1988. At the time, he was working full time in marketing research for Picker International Inc. and part time for Cloonan and Sons. "It was fun because it was my first job," Wilson said of his employment with Picker. "I had a computer and an office, but I wanted something else." He said he has turned AQUA DOC into a comprehensive operation using sophisticated, environmentally sensitive techniques. The company will employ three full-timers this year, including a degreed biologist, and two part-timers. Wilson is licensed by the U.S. Department of Agriculture and uses chemicals approved by the U.S. Environmental Protection Agency. "Every year it's growing," Wilson said of the business. "Adding a biologist this year will make it even better." The bulk of AQUA DOC's business - some 80 percent - comes from contracts to maintain existing ponds and lakes. The company also digs ponds and installs beaches, docks and floating water fountains. AQUA DOC recently expanded into the area of ornamental waterfalls and ponds, a business traditionally dominated by landscapers. AQUA DOC had maintenance contracts for 300 ponds as of April 1, 1994, with more expected by the end of the month, Wilson said. Among his maintenance clients is Lake Farmpark. Sally Hoskins, assistant administrator for Lake Farmpark, said she has hired AQUA DOC in each of the last two years to remove duck weed from the park's three ponds, two of which are visible at the park's entrance. "There was a green layer of plant material covering the ponds," Hoskins said. "This created a problem in that it looked terrible. As people walked up to the Visitors Center, they'd see this green layer on the pond." The duck weed also presented a practical problem. The ponds are part of the park's septic system, and the duck weed was clogging drainage. "(AQUA DOC) solved the problem," she said. "It was immediate." Wilson said he is starting to explore controlling algae biologically by introducing into ponds natural enzymes that eat the nitrogen that algae thrives on. Wilson said his only true competition in this area of pond maintenance are part time employees and do-it-yourselfers. "People don't know where to go," he said. "They're getting bad advice. ...Everybody's scratching their heads about what to do with their ponds. We'll come out and give free estimates on anything. I'm interested in letting people know there's a solution."