This is a discussion on Water change history within the Advanced Freshwater Discussion forums, part of the Freshwater Fish and Aquariums category; -->
when did water changes start ?
decades ago water changes were optional, or even less then that
now those who don't do water changes ...
Water changes have been part of the hobby for as long as I have been keeping fish ~30 years. I have never got the impression that water changes were optional. I think with the internet forums, it has been easier for the casual fish keeper (people less likely to do water changes) to interact with obsessed fish keepers (people likely to do more than the required water changes).
Basic chemistry is the reason for water changes. You cant keep putting organics into a close water system and expect the fish to be happy and healthy swimming in their own waste products.
As an old fart I can remember when a common thought was fish added nutrients to the water that they needed.People would remove old water from their tank and filter it through chesecloth and return it to the tank.Consider this was also the time when cigarette smoking was considered perfectly healthy and gas had lead added to it intentionally. IMHO understanding the need for water changes is the greatest improvement in keeping fish made in the last 50 years.I could go on and on with this but I can remember when keeping Cherry Barbs for any length of time was considered quite an achievement. Now get of your computer and change your water(lol).
I was doing water changes back in the 70s and my father decades before that. Now he has seen some changes in the hobby (tried an internal power filter once and didn't like it...back to the air driven box filters) and still keeps a community tank these days. Bearing in mind he was born in 1930 you can only imagine what his first setup was like! Then again I know my grandfather's first tank had a slate bottom and the water was heated by a paraffin burner underneath this. As far as I am aware he also performed water changes. As jpepe1 said, we now have a better understanding as to why water changes are beneficial to the fish even though they have always been performed for one reason or another.
Years ago when I got into the hobby ( late 70's) water changes were reccomended by my lfs's at about 10-25%/ month. Needless to say I had a lot of problems. I found oit on my own that the more water I changed, the healthier my fish were. I settled into a 25%/ week routine before the internet was invented. Wish I had access to the knowledge that is available today. Many fish would have lived longer healthier lives!