Super-Accurate Water Testing Methods

[geekgirl]

ROTFLMAO! Where's the nerdy emoticon when you need one?

Stacey

[Rex Grigg]

I was not being flip in my answer. But when testing kH using a hobbyist test kit worrying about a 5% difference in the volume of water is worrying way too much. First off one has to consider that the test regent is not accurately measured. Not all drops are going to be the same size. Also each drop is worth just about 17 ppm. If the water changes color after say three drops where does that put you?? Somewhere between 2 and 3 degrees of hardness. If you want to get obsessive about it you would increase the sample size to around 50 ml so each drop would only be .1 degree.

[SNPiccolo5]

When I test KH I just do 15 drops, shake it (swirl it around like Rex) and then just do one, swirl, one, etc... I know my KH isn't like a roller-coaster ride and it is very rarely lower than 15 dKH, usually around 16-17...

-Tim

[STAT 007]

We have a topic going about this same thing over on another message board I belong to. One of the guys is in Australia and he put up some pictures and descriptions of a test kit they have over there that looks a lot more accurate in the color-judging area, yet still appears to be quick and easy. Maybe somebody knows how to get them here...?

http://www.fishinthe.net/html/forum/...?p=12316#12316

Also, does anybody have experience with Seachem test kits? They look a lot like the LaMottes.

[Rex Grigg]

Well if you want to be really accurate LaMotte sells a electronic device that will give you great results. It's called the SMART Colorimeter. It runs in the neighborhood of $900. But it gives very accurate results. And a company called YSI also makes a Photometer that gives good results. It's only $985, but if you want the deluxe kit with printer it will run you $2550.

[STAT 007]

Pretty reasonable prices there, Rex. I think I'll look into those... :roll:

For everyone else who's interested in water chemistry, I was going through my bookmarks looking for disease guides when I accidentally stumbled upon this page that talks about exactly what we're talking about here. Towards the bottom it talks a lot about the potential inaccuracy of electronic testers...

http://www.animalnetwork.com/aquafish/reference/af1.asp

[madpiano]

After reading this article I think I may just give up testing my water.... :shock:
I allways wondered why my Tap Water was reading so high in Nitrates. It's propably the Chlorine in the water which is reacting and I was buying RO Water for no reason....


Never mind. I certainly will not spend 1000s of dosh to buy LaMotte or Electronic test kits...

[doooog]

What you need to do about the color determination... get a spectrometer, and run your resultant samples through it, find out what your absorbancy is and compare to the charts or whatever. Probkem is, those deals are PRICEY :-p

~Doug

[STAT 007]

Originally Posted by doooog

What you need to do about the color determination... get a spectrometer, and run your resultant samples through it, find out what your absorbancy is and compare to the charts or whatever.

Oh God, Doug, you're right! I'd probably use a UV-Vis Spectrometer hooked up to a laptop computer so I could save all the data and plot it with Excel or something. :idea:

[doooog]

i would :p but that's just because i have no life and lead a boring exhistance.