Question on using ELOS test kits

[too_tanked]

I've been using some Elos test kits recently and just gotten a few more. All of the ones that I have indicate that the color in the test tube should be read by looking straight down into the tube. But some of the kits indicate that the tube should be held 5cm above the color chart - while some other Elos kits don't specifiy a distance.

Just wondering what people do here - do you hold the test tube above the color chart an inch or so? Or do you place it directly on the white part of the color chart so the test tube is sitting on the color chart? Or is it different depending on which Elos kit you're using?

Here are the kits I have with the indicated distances:

Nitrite: 5cm above card
Phosphate: 5cm above card (IIRC - don't have directions with me)
Amonia: doesn't specify distance
Nitrate: doesn't specifiy distance

Seems to me that they all should be read slightly above the color chart, but I'd like to see what others do.

Thanks.

 

[pillowfish]

I have just always held up the card and the tube basically about an 1" away from each other and then "guess" the color