Originally Posted by denaliwind
Nope, a 1-3 gal tank without filter needs a 100% per week with a 50% change in between.
Everyone is gonna have their own opinions on frequency. True accuracy for each individuals tank is figured out by doing water tests and measuring out the time it takes to notice a spike as these measurements are based on individual betta waste, uneaten food, etc.
Regardless, some fishkeepers seem to wait it out as if it's a chore. It takes me less then 10 minutes to do a 50pct siphon and replenishment on my 5 gallon so am probably the type who does more water changes then perhaps needed but it's not a big deal since it's so simple and fast to do.