@Miami Reef I don’t want to intrude to much on your experiment I’d just like to give you a couple things to take in consideration:
carbon dosing has two effects in our systems.
effect 1. Reduces nitrates and some phosphates
effect 2. It aids decomposers, meaning that It aids heterotrophic bacteria at reducing organics trapped in the system, by accelerating the decomposition process less Ammonia will be produced as the organic matter is transferred in to the bacteria body mass.
one aspect I found recently is that heterotrophic bacteria can’t reduce free ammonia the only way I see heterotrophic bacteria being helpful is by reducing organic matter therefore reducing the amount of ammonia being released into the water column.
A quick answer is yes, if you continue to dose DOC into the system eventually the diatoms will starve depending on how much organic matter is in the system. This is what beuchat and other carbon dosing methods promote although in a system full of coral I find it detrimental as it could starve coral once a system gets fully depleted from all sources of nitrogen (including no3) that’s why he mentions that having detectable nitrates and phosphates is not important.
I believe you could take it much further and make the method more safe for coral by adding the only aspect to the system that carbon dosing doesn’t help. That is free ammonia, only nitrifying bacteria and phototrophic organisms can reduce it.
If we were to put it all together I would say:
1• keep adding nitrates and phosphates to the system wile using the carbon dosing
this will ensure that there is a source of nitrogen for coral to survive the treatment and ensure that heterotrophic bacteria doesn’t get limited for growth and division. By doing so you would be targeting only the organic compounds unfortunately as a result during treatment no3 and po4 will also be used and therefore would need to be topped up as needed, through conversation we had earlier most will agree that phototrophic organisms will require to use more energy to use this form of nitrogen.
You would also need to have a protein skimmer to remove those nutrients from the system.
2• targeting free ammonia with Chemotroph and phototrobhic organisms
this is we’re you could get creative as there is many organisms that would work here.
2.1• bottled nitrifying culture like one and only by dr. tims or adding cured live rock with good populations of nitrifying bacteria, this can be done by curing new rock in a vat and only feeding ammonia to it ensuring that there is no phosphates or nitrates on the water to limit the heterotrophic bacteria growth in those rocks.
2.2• silica dosing to promote diatoms (phytoplankton really uses ammonia well) and copepod or snail to eat those diatoms transfer the energy into the mass of those organisms.
2.3• live phytoplankton dosing during the photoperiod of the tank, this will allow for the phytoplankton to assimilate some nitrogen forms wile in suspension in the water column once the phytoplankton perish the carbohydrates content will stimulate heterotrophic bacteria and aid the decomposition of organic matter.
The information above is one of the reasons I mentioned earlier in the thread that dosing ammonium chloride to mimic reef conditions would affect your results, we would be skipping the step of adding organic matter to a system and skipping this process could give a wrong idea of what’s happening in a system that is actively being carbon dosed especially if we take in consideration that DOC won’t reduce free ammonia directly.
if you were to take this information into consideration you would not just beat dinoflagellates in your experimental system but would also eliminate the algae, and if you were to continue with a DOC maintenance dose you would also observe that you may not need to use GAC as often in the system. Reason being that organic compounds are being disposed more efficiently from the system compared to just using mechanical filtration. This is the reason I haven’t never needed to use both gac and GFO in mine.
hope you don’t feel I’m intruding to much, your success could be fairly beneficial for the hobby
