Gainesville City Council rejected a couple’s request Tuesday to change an original zoning to allow a fourth residential lot on Lake Knickerbocker, a high-end neighborhood off the Chattahoochee Golf Club. The petition from Tread and Deborah Syfan was denied following objections from several residents, whose complaints included worries the move would negatively affect the lake’s heavily silted waters. “It appears to me that (residents) feel that they gave you what you wanted to start with and now you want to do further,” Councilwoman Myrtle Figueras said.