High accuracy phosphate testing at future meetings - Ca, Mg, and alk also improved

[Greg Hiller]

Hanna donated to our club a special phosphate testing kit/photometer, good for accurately measuring phosphate levels as low as about 0.02 ppm. The donation was facilitated by one of our members, Jessica (xp964).

Also, the club's testing methods for calcium, magnesium, and alkalinity have been improved. Alkalinity will now be measured in the same way that alkalinity is actually defined: Titration with hydrochloric acid to pH 4.2 as measured by a calibrated digital pH probe. The calcium and magnesium test methods have also been standardized and compared to artificial saltwater standards made up in the laboratory with exact and known concentrations of calcium, magnesium, and alkalinity. At the past meeting the calcium and magnesium tests were reading about 15% low. The alkalinity test was also in error, but this has been corrected.

If you want your water tested please bring a 250 ml sample of water to the meeting. A donation to the club of $5 gets you all of the following tests performed:

Salinity by calibrated refractometer
Alkalinity - Titration with 100mM hydrochloric acid to pH 4.2
Calcium - Modified total hardness Hach kit - compared to standard with known Ca conc.
Magnesium - Modified total hardness Hach kit - compared to standard with known Mg conc.
Phosphate - Hanna low range PO4 test kit/photometer

 

[~Flighty~]

Great chance to test our home kits against the club's calibrated kit.

 

[Greg Hiller]

A bump for some more visibility.

 

[SaltCreep]

Who supplies the HCL and the burette for the titration?

Man...I think I may have to join....

 

[Greg Hiller]

HCL at 10 Molar strength can be purchased from the hardware store (Muriatic acid they call it) for about $5 a gallon, FWIW. A 1 ml syringe is used to do the titration. No glass burettes required.