Nooooooo......!!!!
Nooooooo......!!!!
So I'm giving up on the pellets. While nitrates have been brought to a super low level (<0.1ppm), I still get cyano elsewhere in the tank. It's been at this low level for almost a year, yet I still have cyano all over. Never had cyano before this year either. I agree with Randy, the carbon or the bacteria themselves are not being sequestered. I'm down to about .5cm of pellets in a 29g and my last experiment will be to see if keeping a very small amount will balance things out. Otherwise I'm switching the reactor to GFO in the future. Lost too many corals during this experiment and only gained a lot of sponges.
I also need to add that providing amino acids such as Aspartate and Glutamate didn't help shift consumption of phosphate fast enough to counteract the cyano's accelerated growth.
.....don't leave my friend... I too am having issues with cyano. I've suggested in the past that it has at least some relationship with pH. I licked a couple of outbreaks in the past (one on a vodka system, and the other on bp); but have unfortunately had a relapse on the bp. The vodka system is still fairly cyano-free (maybe just a few small traces)... Here are the params of each:
Vodka System
NO3: 15ppm (and dropping after a short break from EtOH [was 0ppm 4 mos ago]
PO4: .34ppm
dKH: 7.5
Ca: 420
SG: 1.025
pH: 8.05 - 8.15
Biopellet System
NO3: 0-2ppm
PO4: 0.07ppm
dKH: 7.5
Ca: 460 (due to pH; see below **)
SG: 1.025
pH: 7.80 - 7.95
** As a result of pH reaching as low as 7.8ish, calcium has been rising from 420 even though no calcium has been dosed in any form.
I've spent a good couple of hours today blowing cyano off he rocks and vacuuming up the matting on the substrate (via a water-change routine); and have now re-instituted a lot of splashing at the point of entry into the sump from the DT. This usually raises the pH up to about 8.08-8.18 or so. I believe this raised pH was coincidental with my previous success in licking the cyano problem of the past.
It is a known fact by now that the bp as well as any other system of carbon dosing does have a lowering effect on overall pH. The pellets respirate just like any other type of fauna in my opinion, and in terms of biomass, the bacteria sustained by carbon dosing can quite conceivably pose the single largest impact on your system's respiration cycle. Remember, the bacteria population created by these pellets utilize C, N, P, and
O, and as far as I can guess, anything that respirates O, exhausts CO2, thus the drop in your pH.
In a nutrient low system such as created by your biopellets, cyano bacteria... the fauna that has the ability to photosynthesize (which is a process dependent on CO2) in my unscientific opinion becomes top scavenger of excess organics and other useful trace elements.
I seriously think that the difference between a system successfully running carbon dosing (whether bp or liquid form) without cyano consequences, and that which is riddled with cyano consequences has mostly to do with the address of CO2... My pellet system has an admittedly undersized skimmer, and no refugium... I am therefore going to attempt other means of CO2 expulsion, i.e. lots of splashing, and perhaps even re-instituting a biotower since nitrates are no longer an issue.
If my current mini experiment goes well, I will be able to maintain a pH above 8.1, and hopefully will be able to report another successful battle against cyanobacteria...
Hang on in there Dark Xerox. Give me a couple more weeks to confirm this theory. Will post the results.
Regards,
Sheldon