Originally Posted by
NaClH2O Nut
http:///forum/post/3001199
That is a very debated question. You will get answers from none to 25% a week. I would like to do none. I am doing alot of research on this and the main reason(truthful) that people do them is that is what they were told to do.
The oceans do not do water changes, I know we dont have oceans but we do on a small scale. With the right filteration, bio load why would we need to do a water change?
We can add all minerals and vitamins with supplements. If water stays in correct para. what good can come from new water?
IME the average word on the street is 15% -25% a month.
To answer NaClH2O Nut's question about why we do water changes if all of our levels are kept in balance and we replentish trace elements with supplements, water changes are the only way to export toxins that accumulate in closed systems these toxins can come from minerals leaching from the LR and substrate, fish food, dust in the air, and even the additives you are using to supplement the trace elements. Take magnesium for example magnesium sulphate is a common supplement for increasing magnesium levels. So every time you add magnesium you add sulphate and over time the magnesium is consumed but the sulphate isn't and given enough time with no water changes the sulphate can accummulate to levels that are toxic to your fish and corals.