I just don’t get it. My old flapper was slightly warped, causing the toilet to keep running in the tank ever so slightly. I could not find a flapper exactly like the old one; hence the journey of finding a flapper that dropped not too slow (causing the toilet to flush twice) and not too fast (solved by the nice man at Ace Hardware with the Fluidmaster Adjust-a-Flush Flapper). However, now the water level in the bowl is low (although the level changes slightly from flush to flush). If I put the old flapper back on, the bowl and tank fill normally. I thought I was onto something having the flapper drop slower, but it ultimately was to no avail. I’ll live with it, but if anyone has an answer, I’d sure appreciate it. Thanks!