calibrate my ph meter , there looks like a screw i can turn ?
and i have one pouch of 4.0ph powder ?
there a pain in the royal ass man ,, i aint got the best site so usin that tiny screwdriver to turn a even tinyer scre !! basicaly u mix the powder with some water i would think, i use a buffer solution wheres urs is a buffer powder, u need to imerse ur ph meter in the liquid buffer 4.0 then switch it on and then turn the screw untill it reads 4.0 , then u shud buffer with 7.0 ( neatrul ) and then this is what u call a callibrated pen !! but wait if the water aint roughly 20c then the reading might not b as accurate, my PH PEN is one of the yellow ones there all pretty much the same !!, the more expensive ones callibrate themselves and adjust to the waters temp all at the touch of a button but there a lil pricey !! i am sick of the one i av u just cant trust it enough plus u av to use the solution or powder in ur case to make into a solution and callibrate every time u use it !! a lot of hassle if ya ask me !!! i will invest in a decent one soon coz if u ever av problems wiv ya grow u av to b sure its not ur PH being out !!!!!!!!