Food for thought (and comment)...
Food for thought (and comment)...
GREAT video! It has inspired me to assemble a few wandering thoughts that came to mind throughout my reading and own experimentation over the last couple of months:
I recall seeing, more than a few chapters ago, that it may be possible to have too much flow traveling through a reactor. I also posted my own revelation (also a chapter or two back) when trying to determine whether the pellets were working for me in my setup... without rehashing the details I found that my aquarium bulk water seemed not to budge over 1.5mos. or so of steady operation (though coming from high levels); however when the pellets were removed from my system and isolated in a pail with a power head, N & P levels reached absolute 0 in less than 12hrs. The conclusion that DJ helped me to draw, and was accepted was that the process takes time and is not an exercise of instant gratification, as probably many of us new-rollers might have expected (this 'takes time' premise was also confirmed by Daveandboss' and now staggeringwade's independent experiences).
Added to my described experiments, I also tested the effluent coming right off of the reactor when operating within the greater system, and there was no noticeable difference in N/P going into/exiting the reactor - once again this was chalked up to a function of scale and time. Now about four months into the entire process (although there were a couple of adjustment interruptions, the last of which was for about 2 weeks, while I adjusted my reactor and tripled the carbon regiment instead); there is still no major strides in the fall of targeted nutrients....
I should also add that I am absolutely positive my pellets are in fact 'ignited' with copious amounts of bacteria, in part because of my initial verification (pail) experiment; but also when I had the pellets removed from the system, and soaking in a pail with aquarium water, without a circulation pump, their life-stock quickly reduced to a strong concoction of hydrogen sulfide every couple of days (if anyone was wondering, this is what would happen if you stored your pellets without rinsing them in RO water and drying them off - everything on them dies off in a manner that absolutely tickles your olfactory senses:wildone: and might earn you an eviction notice:blown

.
I would further reckon that although we know this here pellet strategy relies on aerobic conditions for outer-colonizing bacteria, while creating its own anaerobic micro-environments for inner bacterial colonies, I cannot help but reflect on the notes that other denitrators (or any other nutrient reactors for that matter) can be assessed for functionality by assessing the difference in levels between entry/exit... i.e. sulfur denitrators, operate on such a slow flow-through, that 0 levels should be measured off of the effluent. That being said, I would not expect to see absolute zero coming off of a system that has a moderate to fast flow through, however I would anticipate seeing some difference between the in/out levels... no?
Soooo - after all of that background, here will be my next experiment. I'm going to adjust my pellet reactor to
recirculate a large or
even percentage of the water flowing through it with the goal in mind to maintain adequate O2 for the process while allowing aquarium water more time to interact with the bacteria laden pellets.. I'm not sure what the dynamic will ultimately be, but I know that when the same water remained in a pail with these pellets for a few hours, both levels reduced to absolute [measurable] 0. In the end, what I'm hoping to investigate is whether flow-rate/contact time assigned to this process is just as determinant a factor as it is... say, in a calcium carbonate reactor. In theory, I should still be able to achieve good pellet tumbling while allowing for greater contact time with each pass.. I'm aware that perhaps the micro and macro (water) contact time might involve compensations that ultimately cancel out the overall net effect, but perhaps the changing factor is the level of O2 within the reactor... i.e. maybe I can get the anaerobic component to do a little more work if [by hypothesis] that is where the bulk of the reduction work takes place.... Again hypothesizing, perhaps the tumbling's greatest contribution is in sloughing off of bacteria, and perhaps when there is too much tumbling going on; the outer aerobic layer is dislodged at such a rate that it doesn't allow the anaerobic colonies to establish fully... what if slightly lowing the oxygen level within the reactor would allow the same tumbling/slough-off effects; while reducing the risk of stagnant, hydrogen sulfide favouring conditions to take hold; yet still improving on the efficacy of the anaerobic component... ??? !!! :idea:
Just a theory at this point, but please feel free to let me know your thoughts & comments... or even if you think I'm fishing with holes in my grey-matter... I mean net:sad2:
as always,
Sheldon