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.
The AMA and the ADA suggest that one to two cups of coffee per day is a safe amount (approximately 100â200 mg of caffeine), but in reality you may be sensitive to less or able to safely tolerate more.