water changes and other questions for the DOC!

[tinycrazycrawler]

Hi. I've tried to add freshly made salt water for a little water change (idea read in Korallen *Knop*) and I've had both times RTN for little frags of Seriatopora and Stilopora (Acropora unaffected). Is nearly impossibile to say that the rtn was triggered by the new water, but this was the only new in my tank...
This can link to your studies? Maybe freshly made salt water (done minutes before) is much more aggressive, as I've read in the past, but is so for the toxic metals?
And, another question: reading your last study on reefkeeping seem that the worst thing that we can do for the toxic elements is a water change. Maybe the persons who never change the water are in a better situation? What do You think about? Is difficult now to explain why we change the water. Now no nutrient (po4, no3 ) problem there is in a DSB-live rocks aquarium. Some is harvested. Some is taken out by activated carbon... Maybe, despite toxic metals, there are other toxins (coral toxins?) taken out by a water change?
What is sure is that i've seen sometimes tanks flourish after a water change. Why?

 

[rshimek]

Re: water changes and other questions for the DOC!

Originally posted by tinycrazycrawler

Hi,

This can link to your studies? Maybe freshly made salt water (done minutes before) is much more aggressive, as I've read in the past, but is so for the toxic metals?

Water isn't aggressive. However, freshly made water may be significantly more toxic, as it will have high concentrations of many heavy metals. If these get detoxified by bacteria, or some other means in a holding or mixing vat, then older water would definitely be better.

And, another question: reading your last study on reefkeeping seem that the worst thing that we can do for the toxic elements is a water change. Maybe the persons who never change the water are in a better situation?

Quite possibly.

What is sure is that i've seen sometimes tanks flourish after a water change. Why?

Well, my studies looked at only metals, and perhaps the accumulation of organic materials is equally toxic or maybe even more so. If the water change lowered this, then the tank might be in somewhat better shape after the change.