gravel substrate

I unfortunately do not have access to the Walstad book, but have read people's discussions about the methodology used. I want to eventually try a soil substrate capped with gravel, but I've read that large gravel won't hold the soil down well and it will float up into the water column. So what...

I did a little bit of a search through the substrate part of the forum, but most of the answers I found are somewhat vague, and scattered through the threads with a couple of conflicting thoughts. I'm hoping I can sort of aggregate the answers here. Right now, in both of my tanks (2g, 10g) I...

So I decided that I wanted to start growing aquarium plants, and decided to remove all my gravel. I actually had to separate the two different colored gravels by hand, so there might be a few bits here and there, cause they were once mixed. (took about 3hrs to separate) Anyhow these are the two...