Yes way too soon. Your screen name really suits you,lol. Don't worry about the diatoms. They are ugly and it sucks, but they will go away. Just get your 20 gal QT sorted, and let everything play out for a month or two. Will give you time to save up for the next purchase. I just picked up a used 125 today that will replace my 40 and 55. Got 200 lbs of live sand with it. Was a deep sand bed, and had to pull it all out to get the tank down to a weight that was liftable. I'm gonna have to let that sand brew for months before I'll be able to use it.