Put it this way, I only do water changes when I feel like it. Sometimes it goes months without it. Why? because I have proof and understanding that fish can tolerate more than what majority here believe. You guys take everything at face value. If someone says 20ppm nitrate is the threshold everyone gets OCD about water changes. People also want to act like elite fish keepers. truth is, no one gives a damn about your fish and your fish keeping abilities. Get off your ego trip. MANY fish live, thrive, and survive in crappy water conditions. There is proof out there proving this time and time again. None of my fish die with my lack of water changes. Go ahead and continue to waste time, money and energy all because of your ignorance. I have been keeping fish for many years, I've kept a wide range of species, have bred many species, and this is how I keep my fish and will continue to do so.