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.
Scientists consider that two or three cups of coffee a day would be of no harm to your health. Approximately four cups of coffee a day are quite appropriate, dietitians say. But the excess of the stated dose can have negative consequences. Caffeine increases heart rhythm and enhances pressure.