Can anyone tell me how much canna flush i use per litre.i have found a few threads and they say use 4ml per litre.This is what canna tell you to use but i have never used what canna says on the label as it is always been nearly double the dose.

Also how do you use it do i stop all nute 2 weeks before harvest and then jus give it the flush and water till harvest, as canna website says before you use the flush to put ph'd water through medium first.so do i have to use plain water before or after the flush has been done each time.