if you have "Hydroplex" please read

buying used hydroplexfor a really good deal, can you please stick your ppm meter in their and let me know what the ppm reading is?

want to make sure im not getting ripped of with watered down solution,

and yes i know each batch will range from 0-25ppm difference

you cant do that. you will have to take, say 10-25ml and mix it a gallon of ro or distilled water to get a reading. a normal meter would not be able to measure that high.