[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [APD] Aquatic-Plants Digest, Vol 28, Issue 7

Scott said:

>I'm just not ready to tell folks that no matter how much
>NO3 you add, it won't prompt algae problems. Nor am I
>saying that you have or have not said that you can add as
>much as you want. 
  Well, I'm not telling anyone that _any_ level of NO3 is okay. But it's so high you kill fish and shrimp before you get algae.
  Both positions cannot be right.
  Either NO3 alone, (not with other combinations of nutrients/CO2 etc), cause algae or it does not.
  Isolate the NO3 dosing, not poor CO2 or poor plant biomass etc + high NO3 dosing.
  So if discuss specifically NO3, then we are only talking about NO3.
  We can easily rule that out by doing isolated experiements to figure out what is really causing the algae, like poor CO2.
  Some might not care.
  They just do their thing to avoid algae without wanting to really know why.
  But this approach tells you far more the real players in this game of algae and plants.
  Just like being able to isolate CO2 from the nutrients(make the nutrients non limiting).
  The same is true for Fe, PO4 and other nutrients.
  The results repeatable and experiement is rather simple.
  This way you can find the limits at the limitation end and the toxic maximum range.
  I'm not saying no matter hwo much, I have set a limit for killing Amano shrimps at around 100ppm for 3 day exposure. 
  If we have a working range for 2-3 days of 5-80ppm of NO3, that's a huge target to hit.
  I personally think plants do better at less than 40-50ppm, 20 seems might good IME.
  But high amounts have never produced algae. So we can say something about that.
  If excess NO3 causes algae, why am I unable to induce algae with high NO3?
  and if high NO3 do cause algae, under non limiting conditions, what is that level?
  Come the heck on, do you really think that the algae are "limited" at 20 ppm NO3?  2ppm of PO4? 1 ppm of Fe?
  What is the upper limit if the algae are not limited?
  Basically so much it impaires the plant and causes toxicity.
  That's a lot and we see this pattern for all the nutrients.
  Either fish die or the plant dies at high levels. But with exception to  NH4, the rest of the nutrients do not appear to have higher levels that  will induce algae. 
  Why is this not true for all the nutrients other than NH4(which is pretty toxic even at low levels)?
  I mean it is a simple thing, you add the nutrient dependent variable  over a wide range till you get algae or add so much you get frustrated  and realize it's way beyond the typical extreme case. Then you try the  limiting ranges.
  From there you get a pretty good idea of the effective range for good  plant growth. Algae inducement is relatively simple to see.
  Either is grows in response to the addition or not. But you must have control of the other variables to test this and see this.
  If not, and if you really believe the NO3 at higher levels causes  algae, then you need to look __elsewhere for the problem__, not the NO3  or the excess PO4, excess Fe, most like a deficiency or lower than  optimal CO2.
  Everyone get complacent, then they get CO2'ed and start thinking funny stuff about PO4/NO3/Fe etc.
  This has gone on way too long in the hobby.
  There might be multiple issues occurring, but we know how to solve that  relatively easily from knowing the __individual components__ range's  and ruling them out. 
  That is how we solved the PO4 issue with algae inducement. NO3 is no different except we have an upper range that kills shrimp.
  Tom Barr 

 Yahoo! Personals
 Single? There's someone we'd like you to meet.
 Lots of someones, actually. Yahoo! Personals
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com