How often to do a water change?

[airbrnebkr]

I have been researching quite a bit and have found a million differant opinions on how often to do a 20-25% water change (anywhere from weekly to monthly). I was hoping someone here could give me their opinion and the reasoning behind it.
Thank you,
Doug

[Cearbhaill]

I wouldn't do 25% weekly- salt mix is expensive! Maybe 10-15% if done that often, 25% if it's only once a month??

It's a hard question to answer.
I know how often I need to do mine- but your bioload and feeding practices are different.
Maybe a good answer is "when the nitrates rise above XX, something looks poorly, or one month has passed- whichever comes first."

How's that for covered bases?

[airbrnebkr]

That actualy helps a lot. Thank you very much.
Doug