I've closely observed my toilet and it is using too much water per
flush. I watched the meter outside while my son flushed the toilet
and it used 6 gallons rather than the 1.6 gallons it should! Prior to
flushing and after the bowl is filled there is no movement at the
meter so I know it isn't leaking. After watching it flush I've
noticed the flapper takes a long time before it closes. I've adjusted
the chain float only to find it doesn't make a difference. There
seems to be water and/or bubbles coming up through the drain hole in
the tank and it keeps the flapper open for a long period of time.
Only after about 30 seconds does the flap close and begin filling the
tank again. What can be done to resolve this? Where could the water
or bubbles be coming from?