W/C's and drop in SG

[Captainhemo]

Really give those hydrometeres a good couple of bumps and make sure it is sitting on a level countertoop when you read both when you are checking the tank and when checking you new water before adding it. Just holding the hydrometer at the slightest angle can "bind" the float/pointer and give you an incorrect reading.
As long as your nrew water is at or above the SG of the tank, there is NOWAY the SG can come out lower