assuming the clones are rooted well would start feeding them at a reduced strength at first then increase the strength if they respond well. and start lowering your light a few inches a day if you can, with the ventilation you have now you may not be able to get it very close as it is underpowered for cooling a 1000 and a better blower for cooling the light is something you should do when you can afford to.
you cant really even compare seedlings to clones once a clone is rooted it should take off and start growing much faster than a seedling of the same size ever would and using nutrients is common as they usually can handle it without any problems the only reason you may not need nutrients would be if the soil mix contained sufficient nutrients for good growth for awhile.