Chemical dilution should be done properly, not too much may cause the read value. If the message is too little dilution may result in differences of substance metrix. Make it readable value is not valid.
The dilution should be done right, not too much. May not read the If too dilute May make a difference of substance metrix not make the reading is incorrect.
Diluting agent should be done properly, not too could not read value. If diluted substance too little may make a difference of metrix. Of, make readings that can't be right.