> I want to get a ppm tester but when I went to silvergen.com I read the > price and great god I'm gonna have to spend like 60 dollars to get it. > I remember reading that someone got one for $20-$30 or something but > when I searched the archives....whoa the ppm thread is beyond endless. > :) Ice
Well, Jay, there's value and there's value... The TDS-1 from Hanna Instruments is a good bit cheaper, but it reads from 0 to 2000 ppm. You'll be using it at the *very* bottom of its range, which means the accuracy will not be tremendous. Sorta like measuring grains of sand with a yardstick. Do you see what I mean? That said, I have one and it works well enough. First, it's okay for checking your distilled water. It ought to read about zero. Second, it's been surprisingly accurate and stable, even when making readings on the order of a dozen ppm. It's adequate for ballpark estimates and comparisons from batch to batch. Anyone who wants to claim it isn't hasn't owned one or has some other agenda. Clearly, from the standpoint of matching the instrument's range to the measurement you're trying to make, Hanna's PWT (Pure Water Tester) is just a better choice. It measures to a the equivalent of a couple of hundred ppm, I think, so you're actually in a decent part of the thing's range when taking before and after readings on your distilled water and CS. This better accuracy is why it costs more. It also is calibrated and reads in units of conductivity, microSiemens, rather than applying some arbitrary conversion factor to report PPM. Both meters measure the same thing... the liquid's ability to transport electrons, ei., conductivity. Conductivity is a more honest unit of measure to use in this context. The TDS-1 is just calibrated differently to display ppm. To be fair with yourself you really have to figure out a conversion factor for your individual process. *Whatever* scale factor you use to calibrate the TDS-1, it's not really going to give you accurate ppm readings on your CS unless you do some other kind of testing. Bottom line, Jay, is that we do not have to make this into rocket science. It matters not a whit if your brew is actually 22 ppm rather than 12, or vice versa. Use a good basic process, decent DW and pure silver, clean and sanitary procedures, and dose for effect. If you're in a situation where you think it's critical to know exactly what you have, then you'll be spending a lot more than 60 bucks to find out. Hope that helps! You've come along really fast, Jay. Keep up the good work. Be well, Mike D. [Mike Devour, Citizen, Patriot, Libertarian] [mdev...@eskimo.com ] [Speaking only for myself... ] -- The silver-list is a moderated forum for discussion of colloidal silver. Instructions for unsubscribing may be found at: http://silverlist.org To post, address your message to: silver-list@eskimo.com Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <mdev...@eskimo.com>
