when doing 25% water changes i use the cheapest of them all - none.
but for bigger changes, the cheapest i have found is aqua one water conditioner. $5 bottle treats ~600 litres
i guess one inch ain't that bad but it looked like more.
you're talking to a man that has had 600 litres of water flood his house because he didn't support his tank properly.
after it happens once, you get a bit iffy about these kinda things.
i agree with this article. i only use my heater in winter. but i think it depends on what type of fish you own. as i have americans they are very hardy and i have never had issues with PH swings let alone temperature.
19 degrees is fine for most tropical fish.
i see an animal, i be nice to it. it's not their fault they eat what they eat, and it's not their fault they are here in the first place...
humans on the other hand....
cheers LA i'll stop giving them milk.