PJF, you have repeated the same information again.
The two test tanks are filled with water discarded from a larger system. No new organic material is added. Organic material is taken away by the skimmers.
I am very aware of what you proposed and my comments were in direct response to that. Please stop trying to paint my remarks as if I did NOT understand. It serves no purpose but to cloud the issue.
With periodic testing of the two tanks, we should expect to see the measured DOCs decreasing until diminishing returns are reached.
Would that not be obvious? Of course of you skim organics out of two tanks they levels will decrease in the tested water. The question STILL REMAINS what exactly do you test for? A, B, C, or D? The logic falls apart if you say testing for D should be an indicator for everyting else. You have refused to directly comment on that.
The material collected in the cup will be harder to measure. Bacteria may have modified the contents (see Habib's comments earlier in this thread) and volatile organic compounds (VOC) may have vaporized. Since the goal is water quality, the water column may have the stronger word than the collection cup.
Now we are talking about VOCs... geeze.
And yes, I am aware of Habibs comments about the bacteria colonies in the cup. Please, keep the comments in context to what was said. If we follow your base premises laid out in this thread, then observation of the collection cup is most certainly an indicator. Notice "observation", not "testing". The point is that the TESTS would have to be too complicated.
Repeated testing may be necessary. A Deltec may only best an H&S half of the time in which case the two skimmers may be deemed very close in performance. In contrast, a Bubble King may beat a Remora over 90% of the time.
And if we follow your premise that A, B, C, and D will be skimmed in the order of their solubility and be skimmed a predictable ratio, then we can deduct that the skimmer with the nastiest cup wins. You said you can't have more B than A, C than A orB or D than A, B or C. So the cup that has more D MUST have more of everything else. I hope you see that.
Different test indicators can be used. Some aquarists that use carbon and ozone may prefer a large capacity skimmer that only skims surface proteins quickly and use the collection cup as an initial indicator. Some aquarists may want a skimmer that skims a broader range of organics and not care about the initial rate of surface scum removal.
But we are not testing for all of those things. Of course we could test for a specific set of target proteins. Lets say 10 different KNOWN proteins that range from very soluble to very insoluble. Your contention is that the skimmer that can skim the very soluble proteins is the best. Your logic does not hold up when applied to what we can observe.
Ponder this:
A little 4" diameter 6' tall tube that does D very well but only produces 1 pint of skimmate a week. Set any wetter it does NOT skim D. Does your logic even allow for D to be skimmed before A, B and C are exhausted? Be careful how you answer.
Compare that skimmer to a 20" diameter 1' tall unit that produces 1 pint of stuff a day but NEVER skims any D. It just does not have the ability. Yet it sucks everything else out.
I hope you can see that the SAMPLE size then does matter, as well as a thousand other things.
What is the better skimmer? How do you account for different settings and throughput?
To judge which skimmer is better have to account for its ability to skim ALL compounds, the rate at which it can skim those compounds. How those compouds interact and how the skimmer chooses what bonds and what does not in the column. You just can't do it. There are hundreds of variables.
I submit to you one more time. What exactly is a "good skimmer"? How do you determine the test parameters and what constitutes a winner? Please observe the simple example above. If you think that the example is invalid, the please state why. I ask you to consider the logic though. It will be hard to not contradict your base premise.
I just don't have the time.
