After charging, the battery should cool down the same amount of time it was on charge. During charging, heat is built up inside the battery - the cool down period is to insure the battery is operating a "full" voltage. A battery run a lower voltage will draw more amp & have a shorter life than expected - then it is time to get out the "big" check book ( $4000 -5000 to replace).
You should always inspect each cell on the battery to make certain there is at least some electrolyte covering the top on the cell plates - if not adjust enough to the cell to cover the plates.
When you add water to the the cells do not fill the cells up - only fill to with 1/2" of the bottom of the fill hole. This allows for expansion of the electrolyte due to gassing during the charging cycle.
DO NOT place the battery on charge every night - wait for the battery to become 60-65% discharged before recharging. Think of the battery as have a life span of X amount of charge cycles (some people say 1600). Every time the battery is charged that equals 1 cycle regarding how much is being recharged - it is the initial period of the charging cycle that does the most damage to the cell plates ( the charger is initially delivering a high amp rate to the battery).