"IF" the brix reading was greater than 32 brix, then you may not be able to read the scale, I do not know if this was your problem with the little info you provided, but you may find out by diluting the cream in half with distilled water and try testing it again!
"IF" you are very Acidic , then it may be Best to take it slow with the Detox Full baths and to start out with the foot baths first and then work into the full baths starting with only a 5 min first soak and work up to the 30 min!