"Cleaner" alternatives to dirt?
So I've been extremely successful using MGOCPM in various tanks over the years and am about to set up a new low tech tank.
In this tank, I want to use a lighter colored sand so I'm looking to avoid using dirt because of the inevitability of the black dirt eventually making its way onto the top of my white substrate. (yes, I know the white substrate will eventually become discolored with poop, diatoms, and other normal fish tank things)
So I know about using commercially available root tabs like the flourish tabs and I also know about using DIY root tabs made of osmocote plus and gel caps.
However, I'm wondering about just layering an amount of osmocote plus WITHOUT the gel caps. The only reason the gel caps are used is to deliver the osmocote to a tank that is already filled with water right? If that's the case, then you should be able to simply sprinkle some osmocote into the substrate as you are adding the substrate, right?
Is there a recommended amount of osmocote that should be used? The tank is a 20 long.
Also, are there other alternatives that I don't know about and how effective is the osmocote when compared to MGOCPM?