Hello Randy.
This is not a fish question I'm afraid, but I'm hoping you can help me anyway. I've read your reefkeeping article about TDS meters. (Its the best explanation I've read). In it you have a table showing the 'Relative conductivity of Various Ions' (e.g. Na+ = 1.0). Can you tell me how these figures are calculated or point me to a chart that lists the conductivity of other ions. My personal interest is electrolytic 'Colloidal Silver'. I'm no chemist, but for colloidal silver in distilled water the dissolved ion is Ag+ and I believe the anion is OH-. The conventional wisdom when measuring the ppm of colloidal silver with an ordinary NaCl calibrated TDS meter is to "double what it says on meter". For example if it says 10 on the meter its actually closer to 20 ppm of dissolved ionic silver because "silver is half as conductive as sodium chloride so it has actually required twice as many silver ions to put that 10 on the meter". (I hope this makes sense).
(By the way, the conventional conversion when using an ordinary Electrical Conductivity meter is that 2 uS equals about 1 ppm of NaCl. This conveniently means that when using an EC meter to measure ionic colloidal silver, 1 uS equals 1 ppm. Very neat.).
Laboratory analysis of colloidal silver samples (i.e. actual ppm measurement Vs TDS readings) has tended to confirm this belief that silver is 'half as conductive as salt' but I'm looking for some chemical or mathmatical backup for the idea. I'm sure that somewhere on the internet I have seen a chart that includes the relative conductivity of Ag+, but try as I might, I just can't find it anywhere. If you can help at all I'd greatly appreciate it.
Regards
David O'Neil.
Adelaide , Australia.
This is not a fish question I'm afraid, but I'm hoping you can help me anyway. I've read your reefkeeping article about TDS meters. (Its the best explanation I've read). In it you have a table showing the 'Relative conductivity of Various Ions' (e.g. Na+ = 1.0). Can you tell me how these figures are calculated or point me to a chart that lists the conductivity of other ions. My personal interest is electrolytic 'Colloidal Silver'. I'm no chemist, but for colloidal silver in distilled water the dissolved ion is Ag+ and I believe the anion is OH-. The conventional wisdom when measuring the ppm of colloidal silver with an ordinary NaCl calibrated TDS meter is to "double what it says on meter". For example if it says 10 on the meter its actually closer to 20 ppm of dissolved ionic silver because "silver is half as conductive as sodium chloride so it has actually required twice as many silver ions to put that 10 on the meter". (I hope this makes sense).
(By the way, the conventional conversion when using an ordinary Electrical Conductivity meter is that 2 uS equals about 1 ppm of NaCl. This conveniently means that when using an EC meter to measure ionic colloidal silver, 1 uS equals 1 ppm. Very neat.).
Laboratory analysis of colloidal silver samples (i.e. actual ppm measurement Vs TDS readings) has tended to confirm this belief that silver is 'half as conductive as salt' but I'm looking for some chemical or mathmatical backup for the idea. I'm sure that somewhere on the internet I have seen a chart that includes the relative conductivity of Ag+, but try as I might, I just can't find it anywhere. If you can help at all I'd greatly appreciate it.
Regards
David O'Neil.
Adelaide , Australia.
