We'll I took an SG reading on my batch that should be ready to bottle, 1.02 again. I got my computer out and looked up the suggestions on stuck fermentations, swirled, added yeast nutrient, calcium, etc and now have bubbling in the air lock again. But, I noticed (again) there are many posts about checking hydrometer in water, so for sh_ts and ggls, I did it (I had checked it when my kit first got here and it checked out fine). It read 1.003 in 62 degree water. So, it's been telling me wrong for no telling how long. I always noticed when I would taste the sample, it didn't seem overly sweet to me. Should I just adjust future reading by the amount of error, or replace the thing with a better one? Since it's a closed device, I doubt it is correctable. It sure points out that us noobies really need to read (listen) close to you's guys. Thanks for your help!!