Are there drawbacks to over carbon dosing?

[Winwood]

Close.

If you add acetic acid as the food source, the consumed acetic acid is converted to acetyl-CoA which then enters the TCA energy cycle.

If you add ethanol, the bacteria consumes it and first converts it to acetaldehyde, then to acetic acid which then enters the TCA cycle as acetyl-CoA.

This happens because ethanol and acetic acid are normal byproducts of cell metabolism. We humans produce ethanol in our metabolism, but our liver is obviously able to handle the small amount that is produced.

The cool part about this is that most bacteria can metabolize ethanol and vinegar at dilute concentrations (too high and both become lethal which is why ethanol and vinegar are generally aseptic). So there is no need to "seed" the tank with special bacteria (e.g. nitrobacter)

How much is too much? Well, bacteria can grow in 1.5% ethanol. So if you have a 100 gallon tank, 1.5 gallons can be pure ethanol. :spin2:

You're giving me flashbacks to my Biochem classes at Oregon State! LOL! Thank you for the refresher course, I just hope I don't start losing sleep being haunted by those diagrams again!

I guess it's nice to see some real world application for that stuff though.

 

[jdegrasse]

Lol. And you thought you'd never need to know the Kreb cycle!

 

[Winwood]

Haha! Exactly!

 

[Rovuma]

Bacteria produce a lot of slime when carbon is greater than needed for growth. Slime production is energetically expensive to the bacterium cell, which is why there is an inverse relationship between slime overproduction and cell growth efficiency. Because cell growth is what removes nutrients, overdosing carbon may partly defeat its purpose.

 

[Opcn]

If the bacteria are producing biofilms (slime) that is typically considered a defensive mechanism. As they are better able to defend themselves it's harder for them to be swept back into a food chain. While they aren't necessarily harming anything that way that doesn't mean that they can't be used better.

 

[Ron Reefman]

the main dilemma is N becomes depleted before P when dealing with accelerated N bacterial strains...so you have N become a limiting factor and P will rise or not reduce enough. Also, too much and you get cyano(depending on tank nutrient load) and/or O2 depletion as well...
IMO carbon dosing is best left for a tank that has very low/trace N and P and you want to get to zero... if you have N and P in significant amounts, you have to look at cause and effect vs just carbon dosing to hide poor husbandry/filtration/flow issues.

+1 And the same can be said about other 'treatments like running GFO and/or activated carbon all the time. IMHO

 

[Big E]

+1 And the same can be said about other 'treatments like running GFO and/or activated carbon all the time. IMHO

+1000

A properly designed export system doesn't require crutches or complexity.