Hello, i wanna buy TDS water meter and i wanna ask, how do you think,what about this? http://www.ebay.co.uk/itm/220948461228?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
You'll hear differing opinions. Some sources say 50ppm and less is safe. Other say 100ppm or less. There are plenty of CP growers how have been happily growing their plants for many, many years with TDS measuring between 50 and 100 ppm.