I'm not a fan of that site. Many people will take their 'advice' and it will result in failure. There are a lot of things that site can't take in to account. While it's a fun thing to play around with, nobody should ever use that without seeking the advice of experienced aquarists. If you search the forum, you'll find all kinds of opinions, much like mine.
"What, exactly, is the internet? Basically it is a global network exchanging digitized data in such a way that any computer, anywhere, that is equipped with a device called a 'modem', can make a noise like a duck choking on a kazoo." - Dave Barry