Cycle Question

How do they know that the bacteriostatic effect they are describing is
a result of high NH3 concentration? Is this discussed in the
publication or are they making assumptions?

Does the nitrate production proceed at an increased rate as the NH3
concentration drops? This would support their claim.

It was a controlled experiment that took place under laboratory
conditions.
The variable in the experiment was the amount of NH3 given to the
cultures.
The rate of proliferation of Nitrobacter was found to be directly effected
by the concentration of NH3. So yes, the rate of conversion of NO2- into
NO3- increased in relation to low NH3 concentrations.

Ok. I was not aware of the bacteriostatic effect of NH3 on nitrobacter. I
have not read the article you are referring to, but I will trust that you
HAVE and didn't just read the ABSTRACT.

I was not able to find any other literature support for this phenomenon
which may or not be an indication of the invalidity of the '1972'
publication you referenced.

Going back to the original OP's concern with high ammonia concentration
levels and doing a water change.
I stated that doing a water change would dilute the ammonia and the bacteria
would proliferate more slowly.

If a high ammonia concentration is only BACTERIOSTATIC and not BACTERIOCIDAL
to the nitrobacter than allowing the high ammonia concentration to fall via
the nitrosomonas to NO2- will not cause any harm. (REMEMBER he said his
tank has NO fish yet). Once NO2- begins to form the nitrobacter already
present will begin to proliferate and metabolise the NO2- to NO3-. Once the
NH3 reaches the critical bacteriostatic concentration the nitrobacter will
continue to metabolise the rising concentration of NO2- at their current
population. Once the NH3 levels begin to fall below the bacteriostatic
concentration the nitrobacter will begin to proliferate again and continue
to metabolise the remaining NO2-.

If you REALLY read that article and gave the correct facts, than I stand
corrected and draw the following conclusions:

(A) Performing a water change will dilute the nitrobacter's food source and
slow/stop bacterial proliferation.
(B) Performing NO water change, will allow the NH3 concentration to go up
(nitrobacter proliferation slowed/stopped) and come back down via
nitrobacter.

Both (A) and (B) 'most likely' have the SAME net effect, a slower
nitrobacter proliferation.

If given a choice between changing tank water and doing nothing and having
the same net effect, I will pick doing nothing.

Correction:
(B) should have read "and come back down via nitrosomonas" not nitrobacter.
Oops.

(B) Performing NO water change, will allow the NH3 concentration to go up
(nitrobacter proliferation slowed/stopped) and come back down via
nitrobacter.

Stoutman wrote on 9/22/2006 5:55 PM:
(A) Performing a water change will dilute the nitrobacter's food source and
slow/stop bacterial proliferation.
(B) Performing NO water change, will allow the NH3 concentration to go up
(nitrobacter proliferation slowed/stopped) and come back down via
nitrobacter.

Both (A) and (B) 'most likely' have the SAME net effect, a slower
nitrobacter proliferation.

If given a choice between changing tank water and doing nothing and having
the same net effect, I will pick doing nothing.


Doing a water change percentage sufficient to reduce the
levels of ammonia and nitrite to levels that won't kill
off the remaining life, will still leave plenty of food
for the bacteria. Keep in mind that the rock when pulled
out of the ocean had plenty of bacteria to support a load
of fish. What changed was that stuff on the rock died.
Once the dead stuff is finished rotting, the rock will
once again support a load of fish.

Wayne Sallee
Wayne's Pets

Doing a water change percentage sufficient to reduce the
levels of ammonia and nitrite to levels that won't kill off the remaining
life, will still leave plenty of food for the bacteria. Keep in mind that
the rock when pulled out of the ocean had plenty of bacteria to support a
load of fish. What changed was that stuff on the rock died. Once the dead
stuff is finished rotting, the rock will once again support a load of
fish.

The 'Key' here is doing the correct percentage of water change.

You will have to perform a water change that reduces the NH3 concentration
just below the bacteriostatic levels for the nitrobacter, but not to low as
to stunt the proliferation of the nitrosomonas.

This sounds like a tricky balancing act.

Why bother ? Let it run its course.





Wayne Sallee
Wayne's Pets

The answer is that if it is my rock, I'm going to keep
alive what is still alive. Some people might not be
interested in that, but I have always found that strange.

Wayne Sallee
Wayne's Pets



Stoutman wrote on 9/22/2006 6:12 PM:
Doing a water change percentage sufficient to reduce the
levels of ammonia and nitrite to levels that won't kill off the remaining
life, will still leave plenty of food for the bacteria. Keep in mind that
the rock when pulled out of the ocean had plenty of bacteria to support a
load of fish. What changed was that stuff on the rock died. Once the dead
stuff is finished rotting, the rock will once again support a load of
fish.

The 'Key' here is doing the correct percentage of water change.

You will have to perform a water change that reduces the NH3 concentration
just below the bacteriostatic levels for the nitrobacter, but not to low as
to stunt the proliferation of the nitrosomonas.

This sounds like a tricky balancing act.

Why bother ? Let it run its course.




Wayne Sallee
Wayne's Pets