OK, this is my 2nd post. I'm a firm believer in No Water Changes Needed if you discover the balance. 75% water changes twice weekly???? Really? To me, that is absolutely insane! In my 40 years, I have never done "frequent" water changes. Once every 2 months for years. Fish were big, beautiful, and healthy. Water always had only a slight fresh earthy smell. So why the chemicals? Could it be commercialization has invaded this hobby? Aquarists use to swear by under-gravel filters. But the basic outside bio-filter has proven to be more effective. I don't think this is rocket science folks. If the water needs changed, then change it. But if all your testing says, "Hey, your water is perfect!" Why would you try to fix it? It just baffles me to see well known Youtube aquarists tell you why you need another additive or expensive filtration systems. In my experience, the more basic you keep your tank, the better it is for you and your fish. I'm not talking about marine tanks here. I have 0 experience with them. So if anyone wants to prove me wrong with down-to-earth evidence, I'm all in.