A molecular biologist perspective to the carbon dosing

[BrianD]

Fascinating discussion, thanks to all the participants!

[Tripod1404]

Originally Posted by BlackTip

@Tripod1404

In your opinion, what do you think carbon dosing would do to a tank that has close to 0 nitrate but some phosphate present?

If the tank has very low nitrate, population would become limited by nitrogen availability. However, I highly doubt that any tank with fish can become nitrogen limited. You might not measure high concentrations of any of the nitrogenous waste products such as ammonia, nitrite or nitrate because as soon as these compounds are produced they are consumed by bacteria. The nitrogen in these compounds is either incorporated into new bacteria or converted into another form of nitrogenous waste. This is what we call nitrogen cycle.

Under these conditions, if you have a considerably large bacteria population, it might become phosphorus limited. However, the elemental composition I posted show there is a much lower phosphorus demand compared to nitrogen. This is why carbon dosing first reduce nitrate amounts and after some time phosphate levels start to drop. You need a larger bacteria population to consume all that excess phosphate.

So it all comes down to balance. If you very few fish and feed so little, your tank might become nitrogen limited for bacteria (in my opinion this is very unlikely to happen). For some reason if you have higher phosphorus (like from rock leaching or from water), your tank might not become phosphate limited as long as there is far less nitrogen since the demand for nitrogen is higher compared to phosphate.

[Sk8r]

I will say, after a blackout incident, I started with nitrate well over 100, and using vinegar, managed to get it down to about 50, getting mostly black skimmate, over months. I changed to NoPox, which advertises 'a variety of carbon sources and organic-bonded' stuff. It did seriously work: got down to 10 after 1.5 bottles of the stuff (105 gallon tank). Plus a sump ream-out, toward the 20 mark. Then I stopped the NoPox and changed skimmers for a vastly, vastly more efficient one and immediately knocked it all the way down to 'barely present.' Based on my experience, I'd say vinegar helped a bit; NoPox helped a lot; a sump cleaning helped a lot; and the new skimmer really nailed it down---I wish I'd had that good a skimmer back during the blackout.

I think the dosing did help. And one helped faster than plain vinegar. So did a major cleanout and massive water change. And the vastly better skimmer is what I wish I'd had.

[BlackTip]

Originally Posted by Tripod1404

If the tank has very low nitrate, population would become limited by nitrogen availability. However, I highly doubt that any tank with fish can become nitrogen limited. You might not measure high concentrations of any of the nitrogenous waste products such as ammonia, nitrite or nitrate because as soon as these compounds are produced they are consumed by bacteria. The nitrogen in these compounds is either incorporated into new bacteria or converted into another form of nitrogenous waste. This is what we call nitrogen cycle.

Under these conditions, if you have a considerably large bacteria population, it might become phosphorus limited. However, the elemental composition I posted show there is a much lower phosphorus demand compared to nitrogen. This is why carbon dosing first reduce nitrate amounts and after some time phosphate levels start to drop. You need a larger bacteria population to consume all that excess phosphate.

So it all comes down to balance. If you very few fish and feed so little, your tank might become nitrogen limited for bacteria (in my opinion this is very unlikely to happen). For some reason if you have higher phosphorus (like from rock leaching or from water), your tank might not become phosphate limited as long as there is far less nitrogen since the demand for nitrogen is higher compared to phosphate.

Thank you very much for the detailed explanation. As I understand it, every tank can see benefit from carbon dosing, right?

[Subsea]

I experimented with carbon dosing a skimmerless mixed reef.

Earlier in this thread it was said that phytoplankton dosing was a type of carbon dosing. With that said, so would feeding the tank.

[Tripod1404]

Originally Posted by BlackTip

Thank you very much for the detailed explanation. As I understand it, every tank can see benefit from carbon dosing, right?

I guess it should, unless you mess it up with excessive carbon dosing that results in a bacteria bloom that consumes oxygen and kill the fish

[Tripod1404]

Originally Posted by Subsea

I experimented with carbon dosing a skimmerless mixed reef.

Earlier in this thread it was said that phytoplankton dosing was a type of carbon dosing. With that said, so would feeding the tank.

Subsea, How did carbon dosing work without skimmer? Were you able considerably reduce nitrate or phosphate levels?

[Subsea]

Originally Posted by Tripod1404

Subsea, How did carbon dosing work without skimmer? Were you able considerably reduce nitrate or phosphate levels?

I did not use carbon dosing to reduce nutrients. I used vinegar as a clean source of carbon, to grow bacteria to feed corals and filter feeders. For me it is all about nutrient recycling and for certain, it is a "Question of Balance".

I run high nutrient macro lagoons with mushrooms, softies, NPS and filter feeders. However, If I wanted low nutrients then I would harvest macro as a nutrient export tool.

[Tripod1404]

Originally Posted by Subsea

I did not use carbon dosing to reduce nutrients. I used vinegar as a clean source of carbon, to grow bacteria to feed corals and filter feeders. For me it is all about nutrient recycling and for certain, it is a "Question of Balance".

I run high nutrient macro lagoons with mushrooms, softies, NPS and filter feeders. However, If I wanted low nutrients then I would harvest macro as a nutrient export tool.

I see, that makes sense!

[JonezNReef]

Here is a good read on Vodka Dosing and DSB

http://reefkeeping.com/issues/2004-1...ture/index.htm

[Subsea]

Originally Posted by JonezNReef

Here is a good read on Vodka Dosing and DSB

http://reefkeeping.com/issues/2004-1...ture/index.htm

If I read this correctly, Eric Borneman said in the conclusion section that he would drink the Austin, Texas handmade Tito's Vodka and he would use his 6" DSB to process nutrients and feed his corals.
Looks like the article was written in March 2009.

[sde1500]

Well to be fair, anyone dosing Tito's should be slapped. Hobby is expensive enough as it is haha. So seems like a logical thing to do with the aforementioned products.

[Nano sapiens]

Originally Posted by Tripod1404

The reason for this is the need for anaerobic conditions. For an environment to be anaerobic there need to be little oxygen diffusion to that area. In our aquariums this only happens in deep sand beds and deep crevices of live rock or other special media.

Something I posted on a thread a while back that expands greatly on the sites suitable for aerobic/anoxic/anaerobic bacteria...

Sprung and Delbeek's 'The Reef Aquarium' series (Vol 3) has some well written and informative information regarding denitrification that I found enlightening. Pages. 260 - 261 go into some detail on the subject:

"It has been shown that nitrification and denitrification occur in aerobic layers where they are termed coupled since the processes occur simultaneously, mediated by bacteria in close proximity. Here anoxic microsites provide habitat for anaereobic bacteria, while being surrounded by aerobic pore waters (Jenkins and Kemp, 1984). This is in contrast with the mental concept that the processes occurs in separate aerobic and anaerobic zones."

When a substrate is kept free of excess detritus, the nitrogen cycle can be completed very efficiently.