[cayars]

Originally posted by Boomer
[B]Almost exactly true Carlo and you reading into things again that are not there. Those levels Marc has are way beyond any affect as far as Nitrate up take goes and any limiting effect for any form of marine life using nitrate. Excessive levels way above any normal or even above normal liming will not be affect buy rapid drops. We are not talking here about dropping them to ZERO, another issue. If you want to argue 1ppm, as being excessive and dropping them quickly them maybe. And remember that data in the article is from lab tests and is not from full blown reef tanks, another whole issue.

I mentioned the levels being very low but pointed out I've also read other literature with much higher levels and they agree with my observations of corals showing stress with a rapid nitrate drop. You can't argue with MY OBSERVATIONS. You mentioned it will have no affect on the tank but it does affect many different things including some types of corals that actually like the higher nitrates. Remember not all corals want low nitrates. I'm not even saying he has any of those types of corals but the statement you made just isn't true.

As far as WC goes 1,000's of people have done large multiple WC as I, Randy or many others have suggested with no such effects as you have claimed. 1000's of people do 25-30 % WC / m and is what Randy often suggests to keep ions in balance for sup additions. Your probably were doing something wrong if you had such problems. You need to go back to Randy's article and LOOK at the NO3- levels he is discussing, we are talking for corals NO3 that even <1 ppm is excessive.

Do lots of people do this (large water changes) and get away with it. YOU BET, but people do dumb things all the time and get away with it. That in itself doesn't mean it the best thing to do. While not the same, it's much like dosing vodka in a slow ramp up period and then completely cutting if off. The tanks needs/wants to slowly adjust to the new carbon/nitrogen level, not have it abruptly yanked out from under it.

It's like the old saying "good things happen slowly, bad things happen fast".

Excessively high nitrates are not good for corals and has been shown many times. I have yet seen any tank have problems or even someone mention having problems from dropping high nitrate levels other than yours unless it is a Marco algae tank. I see little of any real problematic algae in his tank.

Just because you haven't seen it happen doesn't mean others haven't. It's your opinion just like my opinion. There are also studies showing some corals like elevated levels and others that show little problem with high nitrates as long as the alk is kept high. It's neither here nor there what they like. The point I'm simple saying is adjust your levels slowly in either direction up or down.

Forget chemistry for a moment and think biological. What happens to the tank when nitrates rise, what happens when they lower?

Most people learn and get "move slowly" with changes to alk, ph, calcium, mag, strontium, iron, iodine, etc but fail to apply the same logic to nitrates. Tanks need time to adjust to EVERYTHING, not just the things we usually think of as "being good for the tank".

Salt manufactures know this and that's why most of them tell you right on the bucket you shouldn't exceed 10% a week or 25% biweekly water changes. Think about that. Why would a salt manufacture tell you not to exceed an amount? If you do they sell more product. They know it's not good for you tank. Not because of the additions (they should be close) but because of delusion effects. To much to fast is not good.

Carlo