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.
They tout that they are as safe as coffee, but maybe not. They have a lot more caffeine than an 8-ounce cup of coffee.. That 8-ounce cup of coffee has about 100 milligrams of caffeine, although coffees and teas vary widely in their caffeine content depending on how they are brewed. For example, CR finds that 8 ounces of Starbucks coffee has 165 milligrams of caffeine. CR says safe limits of caffeine are up to 400 milligrams per day for healthy adults, 200 milligrams a day for pregnant women, and up to 45-85 milligrams per day for children, depending on weight.