y is it that when i get my reading to 500ppm with my nutrients i put the acid in to bring the ph down and the ppm reading goes up to 1200-1300? it makes it really confusing when topping up a 20 litre tank.

cheers
sc0usa Reviewed by sc0usa on . how do u use a tds meter can ne1 please tell me what my tds reading should be,ive just got a meter and its reading 168,dont know if thats right for 4 week old plants. cheers guys Rating: 5