It matters. If they are in veg and your meter is reading 1300 on a .5 conversion that is an EC of 2.6 which could be super hot. (.5 ppm 1300x2=2600. Drop the zero's. 26, add a . = 2.6 ec. If you have one of those cheap tdsXXX brown meters they use a .7 conversion. Should always use EC if you...