Allan writes, The purpose of the filter course is to prevent fine soil medium particles from washing into the drainage layer causing clogging or reduction of the drainage capacity of the drainage layer.
Just how much caffeine is too much? For the average person, up to 300 mg of coffee a day, or two to four cups of the average brewed coffee, is a moderate amount that isn't harmful. But once you hit more than four cups, you may experience less-than-desirable side effects.
So how much coffee is healthy, and how much is too much? Two to three eight-ounce cups per day is considered moderate; heavy coffee drinkers consume four cups or more daily. Remember, the amount of caffeine per coffee beverage varies depending upon the preparation and style of beverage.