Don't know...never used 'em. You can test the run-off water with the ph pen, tho.
I think the TDS (total disolved solids) meter, and the EC (electrical conductivity pens are for hydro, but not sure.
Rusty Trichome Reviewed by Rusty Trichome on . Ph'ing my water correctly? When i mix my nutes i adjust the Ph of the water first, then i mix in the nutes, one at a time. I also am aware that many nutes have effects on the Ph. I fear that my nutes have been throwing off my Ph, which i thought has been a solid 6.5 the whole time. My question is, will i be able to get an accurate Ph reading after the nutes go into the water and is mixed up??? This way i will be able to get a more accurate reading before the nutes go in the soil. If i can take a reading after Rating: 5