why Amano recommended full canister filter filled by biological media? What do you guess about this?
Amano is not an undisputed authority to me. In all his doings, I can sense that he was a very smart marketer in the first place. So, whatever he published about his methods should be read with that in mind.
Secondly, I have not read all that he said and wrote, far from it, but I do know that at least on one occasion he described his filter media differently: half pumice, half activated carbon. Pumice was intended as both mechanical and biological medium, while activated carbon served clearly to keep dissolved organics low. I surely confirm that such a filter might serve him well, especially if he had enough time (or hired labor) and money to employ large amounts of first-grade activated carbon and replace it in short sequence. In any case, all his tanks clearly betray they were cost- and labor-intensive; they required diligent maintenance to preserve aesthetic details as well as biological balance.
Unlike Amano, I'm an amateur without marketing interests and limited budget. At the same time, I have been practicing this hobby for many years. I've adopted a steady pace in doing it. Let me stress one important thing: Everywhere on the Internet, even here, our perceptions are biased by the fact that people participate in discussions and expose their tanks at the time when their interest and care are peaking. A month later their tanks may look very very differently, but we don't know, we don't hear from them.
Seasoned hobbyists, on the other hand, have rather different preferences. Making their tanks able to function for long time, even many years, with modest effort and equally modest expenses.
Lasting balance is our prime goal, not elaborated visual perfection requiring too intensive attention.
So, I've found - and I'm surely not alone! - that to over-do and over-dose things is the safe way to imbalance. Nutrient-rich and similar special substrates? Perhaps not bad for some, but why should I take the risk when I'm not in a hurry? Many fishes of diverse families? Superficial. They'll show their true nature about as well as POWs kept in a camp. Too heavy a burden for stability. CO2 injection? Do I intend to trim my plants every week and sell them in the market? And so on. Experience leads me to making things as simple as possible. Lightweight. With such an approach, strong and sophisticated filters are not necessary. Something lightweight (and cheap) can do basically the same job.
