Re the 'if we could measure something' I agree - but its like Randy says in the intro to his organics article, organics are one of the most difficult aspects of reefing to measure and manipulate. I read the thread you linked but I think its mainly concentrating on removal of nuisance algae. I suppose water clarity might be linked to nuisance algae of course, and in the days when ozone was more popular people used it to improve clarity. I've found ozone to not seem to have a beneficial effect in my tank, but since using vodka water clarity has never been an issue for me. But it is interesting to see the posts above about eliminating patches of GFA.
As for natural reefs I find it hard to believe there are high levels of organics on them, having dived in quite a few myself, although not with a salifert test kit tucked into my weight belt, in the ones I have dived on the water does not have a brown tint, it dosent foam much in the surf, and it frequently seems to run in from offshore deep water areas that seem unlikely to contain much organic matter. Coupled with the numbers in Randys article of NSW reef organics I can't help but think that most tanks might have higher organics than natural reefs, and I wonder what effect that has on sensitive corals, mostly SPS, considering the fact that organics feed bacteria and SPS exist in symbiosis with bacteria living on their 'skin'. Overgrowth of SPS skin bacteria is associated with RTN and bacteria are fed with organics. Hmm easy to draw conclusions but theories are frequently wrong in this hobby. Although some people say SPS respond well to things like aminos, is that mainly because they are running ULNS and just dosing an expensive form of N and P? Might reducing organics and providing stable levels of mineral N and P be worth trying? If so, peroxide might have value in reducing those organics. Having said that, Randy seems to believe that if you want to reduce organics, bacterial methods and GAC are superior to oxidants, and it has to be said he is more likely to know.
As for natural reefs I find it hard to believe there are high levels of organics on them, having dived in quite a few myself, although not with a salifert test kit tucked into my weight belt, in the ones I have dived on the water does not have a brown tint, it dosent foam much in the surf, and it frequently seems to run in from offshore deep water areas that seem unlikely to contain much organic matter. Coupled with the numbers in Randys article of NSW reef organics I can't help but think that most tanks might have higher organics than natural reefs, and I wonder what effect that has on sensitive corals, mostly SPS, considering the fact that organics feed bacteria and SPS exist in symbiosis with bacteria living on their 'skin'. Overgrowth of SPS skin bacteria is associated with RTN and bacteria are fed with organics. Hmm easy to draw conclusions but theories are frequently wrong in this hobby. Although some people say SPS respond well to things like aminos, is that mainly because they are running ULNS and just dosing an expensive form of N and P? Might reducing organics and providing stable levels of mineral N and P be worth trying? If so, peroxide might have value in reducing those organics. Having said that, Randy seems to believe that if you want to reduce organics, bacterial methods and GAC are superior to oxidants, and it has to be said he is more likely to know.