Over the weekend I brewed up an IPA with 3 pounds of maris otter then after mashing used dme for the rest of the fermetables. My OG (and brix) readings showed that I hit my target OG according to BrewersFriend. I took a stab in the dark by using 2/3 RO water, and 1/3 city water with 2 teaspoons gypsum. My question is did I really convert the starch in the grain to sugar just by looking at the gravity of the wort? I don't have a water report to be able to use the proper calculators to know what I should add, and I don't have a PH meter to check the water either. I know I took a stab in the dark with trying to mash, but I had enough dme to add at the end of the boil if my OG fell short.