first impressions

Love help and ideas and advice on what will be the next part of my reefing dreams

I got the magnesium checker about a week ago. It's very easy to use, comparable to the Alkalinity checker in terms of ease of use. There's only one extra liquid reagent to mix with the unreacted sample water, when concocting the "blank" cuvette for C1. When I first got it, I first checked its...