I’ve been fishkeeping for 30+ years and I always had to do water changes. There had to be a better way, so I designed a drip system so I never have to do a water change again. And I succeeded, I haven’t done a water change in 6 months. All my chems are 0 across the board.
I have a lifter pump removing small amounts of water from the main column, as this water is being removed I have fresh water being added at the same time, so the water in the tank is always being diluted. My current rate does a full water change every 5 days. So the dilution is 20% a day.
the water comes from the tap, thru a triple carbon block filter and to a float valve in the sump. as the water gets removed the float lowers and fresh water is added, the same way a toilet works. My fish have never been happier