Re: Biofilter et al

[Thomas Barr <tcbiii at earthlink_net>]

> To sum up a couple of threads -- knowing full well the risks of
> generalizing;
> 
> Injecting CO2 to levels used in planted aquaria won't kill off the
> bioculture, not even when injected in a canister filter

Well, depends if the filter clogs or not etc. If flow is good and
maintained, there really should not be an issue. O2 and CO2 are rather
independent. Bacteria like the O2 which generally is not lacking. The only
thing that might be detrimental is filter lock, clogging and very low pH
which may or may not effect the bacterial colony. I don't think it(low pH)
does much myself although the better rate of biofiltration seem to be around
the slight alkaline level. I'm not going to worry about it for this
application anyhow. If you keep the thing clean and goo flow going through
the filter, things should be fine.
 
> Generally Plants use NH4 *and* NO3, with various preferences for the
> ratio, but they do not use NO2 -- either the plants get the
> ammonia/ammonium or its builds up or gets converted (by the biofilte much
about that effect)
> to nitrites and then to nitrates.

Yes.
Better to have bacteria and plant growth than algae.
> 
> Biofilters provide a backup to keep nitrites down.

And NH4.

> 
> You can run planted tanks without biofilters, but fish loads must be
> severely minimized ("severely" if your the kind of aquarist that likes
> to keep fish) or the ammonia/ammonium the fish produce can foster algae
> growth.

Generally, yes. Some folks don't have fastgrowers, fully planted tanks etc.
A balance between new plant production and fish waste production might be a
better generalization.
 
> Biofiltration can be (generally is) good for planted tanks, especially
> if their is a more than a negligible fish load.

Yes.
 
> I'm feeling better and better about the money I spent on the German
> apparatus, not to mention the French and American ones.  ;-)
> 
> Scott H.

I would not fret over that $. It was well invested and efficient
electrically. As a customer in CA that was raped by Enron and this crap
about privatization of public utilities(that we owned) that are handed over
for next to nothing to corporations(please look into this), I'm far more
worried about what the federal government does with the billions in tax
money and corporate insider deals than that. Shrub: the bankruptcy
president.

I could get a nice German filter for 4 billion dollars.
   
Regards,
Tom Barr