No worries Marc. I didn't intend my comments to sound hostile but when talking about the broader topic of nitrates it is helpful to know people's experiences with methodologies.
As far as the specific product AZNO3 - the thing is, while it "works as advertised" the real concern I have with it is that it is a band-aid. You buy one bottle or whatever, and you use it until your nitrates are gone, and then you stop. That's all well and good, but to me it's the equivalent of a diet to lose weight. The diet may work but if you don't change your lifestyle, the changes likely won't stick. There's an old saying - come to think of it, I think it's from your neck of the woods (Texas) - "If all you ever do is all you've ever done, then all you'll ever get is all you've ever got." Your tank had had a lot of time to accumulate up to 60ppm. Likely, the nitrates bound to your subtrate would leach out after water changes making it seem like the accumulation was at a certain rate - but the reality is it was more likely a more slow accumulation over a long time that got you there. Thus, even reducing the nitrates to zero - you likely won't stay there forever if nothing else changes.
Believe me I know the frustration of inexplicably high nitrates. I was up to 80ppm a year ago - I was desperate for a solution. I banked on sulfur to be my way out of that nightmare - but it wasn't. I agree, this topic isn't about sulfur but honestly the change that going to a ULNS system was so profound to me that I would be remiss not to share my experience when I see others suffering from high nitrates. A year ago had you asked me what I thought about Zeo I might have scoffed and said "bah, it's cheating." But really, similar to how RO/DI levels the playing field amongst geographically dispersed players, aiding and abetting the bacterial cultures that reduce nitrate and phosphate levels the playing field among players with different live rock (let's face it, not all live rock is created equal - why else might someone with say 2 lbs/gallon suffer nitrates and someone with 1/2 - 3/4 lbs/gallon not suffer nitrates - assuming all other variables are reasonably equivalent?). So now I'm like .. is it really cheating - who cares! If it gets your the results you're looking for.
Anyhow, I'm not trying to stir the pot, sorry if it looked like I was. I am just compelled to share my experiences. I came close to quitting the tank because I could not solve the nitrates. Dude, 80ppm sucks. So I know what 60ppm must feel like. I lost corals to the nitrates before recognizing the tank was having a problem. Again, it was more a slow accumulation that crept up on me and by the time I realized what was going on it was out of control. I'm back to being pretty anal about measuring my nitrates - I hope not to repeat that mistake.
Skydancer - I didn't use a commercial denitrifier, I converted a dual stage calcium reactor to a sulfur reactor. It held one full container of Caribsea LSM (sulfur granules), the second stage I just used ARM.
