When I marked the sight tubes on my keggles, I weighed each gallon of water according to what it should weigh at whatever temp it was. It's really the most accurate way to do it.
Next: No idea
Fermenting: Oktoberfestbier, Kolsch, Homegrown Hop IPA 2015, Doppelbock, Egregious-ish, Barrel Fermented Dreg DelcoLambic, Sacch Trois Helles
Drinking: Oat & Conan DIPA, RIS, Carrot Blossom Cedar Mead, Dusseldorf Altbier, Cider, Rye Berliner Weisse, Sauerkraut Fermented Gose, Gueuze, Brett Blonde, Kriek, Saison, Sour Blonde
Barrel aged: RIS, Rye Barleywine, Tripel, Wee-Heavy