Macronutrients and Micronutrients?

[rkilling1]

What are these? (in reference to aquatic plants)

Now, that may sound like an easy question, but I assure you the answer will not be an easy one.

I have spent the better half of the night researching this very question and still have not answered it fully. (that's what you get when you have paid sick time, LOL)

OK, let me begin with what I am talking about. I was researching plant deficiencies and one of them was sulfur, but I did not know S was either a Macro or a Micro Nutrient for a plant, and that is what started the search. Upon researching this, many different resources list different Macronutrients and Micronutrients for aquatic plants.

You see listed on AA the standard N,P,K and just "micro's" all the time. I have NEVER seen S mentioned here as referenced as a micro or macro Nutrient. (ok LWB mentioned it once.search is your friend)

A lot of sites list N, P, K, C, S, Mg, and Ca as the Macro's and Fe, Mn, Mg, Zn, Cu, Mo, and B as the Micro's.

I would only have to assume that some plants need some macro's more then others, but wouldn't you want the full marco's in your tank regardless? We as AA members do not know what species of plants are going into other peoples tanks right? or is it because S is always available in my tank already? like Ca++ and Mg++. I dose K2SO4, so I have S available, but what if I didn't?

(for the heavy guys/gals what makes each one of these a macro/micro and for which species of plant? and for which part of the plant? maybe all 4 volumes of the AGA guides would help.(yes, it really has been that long of a night))

references: (good reading, I hope. the only ones I remembered to save.)

http://www.aquatic-gardeners.org/elemental.html

http://www.aquabotanic.com/glossary.htm

http://animal-world.com/encyclo/fresh/plants/PlantWaterMaintenance.htm

http://www.ncbi.nlm.nih.gov/entrez/...ve&db=PubMed&list_uids=15158029&dopt=Abstract

EDIT: I do see that my root tabs contain 12% sulfur.

 

[Purrbox]

The Macros and Micros in our ferts are the nutrients that are most commonly not available in sufficient levels in our tapwater for the plants. They are not a complete list of all Macro and Micro Nutrients, just the ones taht we commonly need to dose. I've seen a few different articles that give a full list of the nutrients that plants use, but it's been a while and I don't remember where I saw them right off. I'll go digging another time when I'm more awake and see if I can find them for you. (FYI - Carbon is considered a Macro Nutrient.)

 

[rkilling1]

The Macros and Micros in our ferts are the nutrients that are most commonly not available in sufficient levels in our tapwater for the plants. They are not a complete list of all Macro and Micro Nutrients, just the ones taht we commonly need to dose. I've seen a few different articles that give a full list of the nutrients that plants use, but it's been a while and I don't remember where I saw them right off. I'll go digging another time when I'm more awake and see if I can find them for you. (FYI - Carbon is considered a Macro Nutrient.)

that was anothe late night for me Purrbox. my REAL questions are:

Why are we, here on AA, not calling the Macro's N, P, K, C, S, Mg, and Ca?

And why have I not heard about Sulfur?

"Green plants deficient in nitrogen, sulfur, or iron develop a similar yellow coloration. In each case, the yellow coloration is accompanied by a lowered chlorophyll concentration."

http://cat.inist.fr/?aModele=afficheN&cpsidt=2310015

here is a fun one:

http://www.pondkeeper.com/archive/ArticlePDF/2003-03FAQ.pdf

seems the more I look into Sulfur, the more I realize how important it is for the plants to consume.

"I'll go digging another time when I'm more awake and see if I can find them for you."

I would appreciate it.

 

[Jchillin]

Interesting. I have always seen Macros listed as N, K, P, Mg and Ca. You are right, I rarely see a reference to S. However, I have always used This link as a reference tool and S is listed very prominently.

The other thing is that as you stated, K2SO4 is continually mentioned as a necessary nutrient for dosing on this forum (like you say, search is your friend). The possibility is, since members seem to know what the ingredients in K2SO4 are, it's not mentioned separately.

We can always change that.

 

[rkilling1]

The other thing is that as you stated, K2SO4 is continually mentioned as a necessary nutrient for dosing on this forum (like you say, search is your friend). The possibility is, since members seem to know what the ingredients in K2SO4 are, it's not mentioned separately.

We can always change that.

If you maintain a relatively low fish load the K can be maintained by KNO3 alone, so the addition of K2SO4 for some people may not be needed. This is another reason why I am reasearching this.

http://www.barrreport.com/articles/...rce-k-no-k2so4-kcl-needed-ratio-analysis.html

EDIT:

Lets see if I can beat this dead horse even longer. LOL

lets take Duckweed for example. (Lemna minor)

"A native photosystem I (PS I) complex and a PS I core complex depleted of antenna subunits has been isolated from the uniformly 14C-labeled aquatic higher plant, Lemna. These complexes have been analyzed for their subunit stoichiometry by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis methods. The results for both preparations indicate that one copy of each high molecular mass subunit is present per PS I complex and that a single copy of most low molecular mass subunits is also present. These results suggest that iron-sulfur center X, an early PS I electron acceptor proposed to bind to the high molecular mass subunits, contains a single [4Fe-4S] cluster which is bound to a dimeric structure of high molecular mass subunits, each providing 2 cysteine residues to coordinate this cluster."

As you can see/read, the subunit consists of an iron/sulfur cluster. This plant would not suvivor without S present. (well truthfully, I do not know that.)

http://www.ncbi.nlm.nih.gov/entrez/..._uids=3284885&query_hl=16&itool=pubmed_docsum

 

[czcz]

If you're a subscriber, FYI March '06's BarrReport Newsletter is on S and its forms. I'm still on 2005 and have little to contribute.

is it because S is always available in my tank already? like Ca++ and Mg++.

I think you're on the right track here. Barr suggests a 2:1 P:S or ~15:1 N:S could be used as a "generalized ratio." If we just call it ~1-2ppm SO4, most anyone dosing MgSO4, CaSO4, or K2SO4 would reach the target.

CSM+B and Seachem Flourish, many root tabs (including Seachem) have S. I'd bet lots of other products do too.

Also FYI, both Barr and Walstad state S will take many forms in the water column and substrate.

 

[rkilling1]

Thanks CZCZ that helps tremendously.

Both Barr and Walstad state S will take many forms in the water column and substrate. Unless it is RO/DI I would guess the average aquarist with the average tap could move forward with the other Macros.

Did they happen to mention that with the newer emissions laws, that S will be decreasing in our water supply?


seems as though a lot of my questions would be answered if I would just subscribe to the barr report.

 

[czcz]

Edited that out after having the same thought Once excess S is in the water column (say, from a fert or the pipes in the home or something), it's breaking down and taking forms and recycling, though. I believe the anerobic pockets sand users try to avoid is H2S, for example.

BarrReport Newsletters are sweet. He writes them in an easy to understand yet professional way, with tons of information for cross research and reference. The time it saves from searching the net for Plantbrain posts alone makes it a bargain