You’re hilarious @Emilya . I’m so happy I know who you are.There are a lot of people out there making youtube videos who have no idea what they are talking about. They make it sound good, but the old idea of giving plain water at the end for 2 weeks has been debunked. It is passe... It is old discredited science.
There is never going to be a day when my expert advice is not countered with 10 youtube videos made by people with lots less experience than i have. On the other hand, I have never made a video, so the video online world is definitely in a deficit situation when it comes to what I know and teach in my writings.
Yes, unfortunately there are mixed answers out there. Since you can not follow all of the advice, your task is to find someone's to follow who seems to have a logical way of explaining things, and who probably has a huge following on a forum somewhere. If that person really knows their stuff, they would have tons of grow journals and tutorials trying to share their knowledge. They would have writings online that were shared by users all over the globe and they could have articles that were read 70,000 times, or so. A truly knowledgeable person would probably have lots and lots of followers, and would be writing many messages per day about their craft. A person such as this may have even been voted by their peers at some point to be a member of the month on one of the forums somewhere. Find that person. Follow that person's advice... even if they don't have a flashy youtube presence.