I've avoided root tabs because most of the capsules I've seen look like they have Osmocote in them which I don't think dissolves. The chemicals inside them do, but the pellet itself doesn't. I don't want those little balls on and in my substrate. I've used APT Jazz. I just shove them down into the media, but to be honest, it looks to me like it's just APT Feast put into a capsule. I could be wrong, but that's what it looks like. They are crazy expensive, so I'm not buying any more. I've just been putting spoonfuls of APT Feast around where I feel it is needed. You can buy empty capsules on Amazon and make your own APT Jazz if you want.