Let's settle this once & for all: Do you *really* need water changes, or is it just aquarium folklore passed down like some wet religion? Spoiler alert—the answer is "it depends," and that's exactly what makes this fascinating. I'm here to teach you the science behind both approaches so you can make informed decisions for *your* specific setup. Whether you're running a high-tech CO2-injected masterpiece or a low-tech Walstad-style ecosystem, understanding water chemistry is your superpower.