Quote Originally Posted by WeedTree's
Can someone explain to me Total Disolved Solids, Parts per Million, and EC? I know readings are different for different nutrients/rez. sizes etc. but is there a general rule of thumb what should be what?
Sorry I was medicated.

Do you want to know the mixing of GH 3 part. Like the PPM mix number of ml per gallon of water ?

latewood has a very good modified Lucas formula. The lucas works good but latewoods is better for me. When we first started I think we did GH 3part like 1-2-3 then in flower turn to 3-2-1 at 5ml to 15ml per part per gallon of water. Depends on how strong you want it.

This is why the meter is sooooo important. Other wise your really flying blind.

TDS. EC. and PPM are all the same thing. Ec is electrical conductivity measured in the solution which we figure total disolved solids from which gives us a parts per million counts.