Are these 'High Tech' substrates actually worth it? I've kept aquaria for over 40 years and I've seen the wave of enthusiasm sweep through the hobby for these new (and very highly marketed)'super substrates'. Is the enthusiasm justified? Did aquatic plants form a union for better conditions? Did I miss the memo that aquatic plants will no longer grow in plain gravel and fish poo? What happened to the old 1mm, 2mm, 3mm gravel substrate loaded with fish mulm and root tabs under root feeding plants and dosing the water column? I've never used these 'super substrates' and have always had excellent plant growth (actually too much, as sometimes it can be a chore keeping up with the growth) and my compost bin takes a lot of aquatic prunings. Am I being too sceptical in thinking that "Wow, these companies are making a killing selling dirt"? What does one truly get for paying 10x-15x the cost over 'old fashioned' substrate? What am I missing out on by using plain old gravel?