Refractometer and Spirulina powder

Hi all!

How do you test BRIX for powdered spirulina powder? I tried to mix some with water and put some drops on the refractometer and the BRIX reading was 1. The same with ground nettle powder mixed with water.
The spirulina is suppose to have high quality, I personally emailed the manufacturer and he told me where it was is grown, and how it is handled speciallay to preserve the vitamins/minerals.

By the way, I bought some radishes the other day, they had BRIX 2! :(


Thanks in advance!

//Monika Tweet