Aquatic Plant Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
1,710 Posts
Discussion Starter · #1 ·
Has anyone tried using humic acid in their emmersed setups? I got some from a landscaper friend of mine and its supposed to be really great for terrestrial plants. I was thinking of adding some to the water in my emmersed tray. Any thoughts?
 

·
Registered
Joined
·
143 Posts
Peat contains humic acid right? If I'm not wrong peat is often used as a soil additive for terrestrial plants.
 

·
Registered
Joined
·
1,710 Posts
Discussion Starter · #3 ·
Yes i believe peat does contain humic acid. That probably means it will be okay to add it. Thanks :)
 

·
Registered
Joined
·
201 Posts
Sir_BlackhOle said:
Has anyone tried using humic acid in their emmersed setups? I got some from a landscaper friend of mine and its supposed to be really great for terrestrial plants. I was thinking of adding some to the water in my emmersed tray. Any thoughts?
Added as a liquid suppliment? As already pointed out, peat contains plenty of humic acids, but I think this might be a little misunderstood... Humic acids refer to a class of chemicals, just like tannins, its nothing specific... sort of like saying something oxidized -- this isn't a very scientific description of something. You generally resort to saying stuff like this you when have no idea whats really going on.

From a website I found:
Humic acids - the fraction of humic substances that is not soluble in water under acidic conditions (pH < 2) but is soluble at higher pH values. They can be extracted from soil by various reagents and which is insoluble in dilute acid. Humic acids are the major extractable component of soil humic substances. They are dark brown to black in color.

This comes back to that all peat/soils are not created equal problem... something might work great for you, terrible for someone else and at the very best you're not being specific or scientific and unable to attribute success to a particular variable. As far as beneficial versus essential, I'm in the absolutely opposite camp from Giancarlo here, theres a section from an old African Violet book I would like to share with everyone, as he makes the argument better than me... I'll post when I get home.

Anyhow, amino acids, vitamins, growth hormones, etc, etc, I personally consider all of this worthless. Its my personal feeling that something like an amino acid added to the tank will probably only be broken down by bacteria, converted to nitrate, then taken up by your plants. There have been tons of studies, none of this stuff has been shown consistently effective. I think the most simple solution is best, and the most simple solution involves adding as little as possible to your tanks/emerse fert mix.

Jeff
 

·
Registered
Joined
·
1,710 Posts
Discussion Starter · #6 ·
Its water soluble. I was going to add a small ammount to my emmersed tray and see what happens. I would like to read that article though :)
 

·
Registered
Joined
·
201 Posts
Well, I found the book, read the section on the vitamin myth once again...it wasn't that good :) It was the justification for reasonable pesticide use that was excellent. Anyhow:

"The first question that comes to mind about knowing the sixteen essential plant food elements might be, 'Who cares?'. You should care! Too many times, growers will buy a fertilizer for their African violets without really understanding what chemicals are present in the product.

Why waste money on a fertilizer that makes claims of having vitamins, proteins, and other exotic chemicals in it that are absolutely useless to an African violet plant?

<snip>...do not pay for something the plants will not use....<snip>

The addition of vitamin B1, or any other vitamins for that matter, to the potting mixture has absolutely no effect upon the growth of an African violet plant.

It is true a plant uses vitamins in many of its essential metabolic functions, but they do not absorb them from the potting mixture or through their leaves. The plant absorbs all sixteen of the essential plant food elements and uses various ones as building blocks to manufacture the vitamins needed for its normal growth.
"""

The book, altho it seems very targeted to AVs, it the best all around horticultural reference I own. It has the fert/potting medium writeup, it gets into CEC of potting mixtures, deficiency symptoms, Mendelian genetics, flower anatomy, etc... all of this is very general stuff.

African Violets: Gifts From Nature, Melvin J. Robey, Cornwall Books, New York 1988, ISBN 0-8453-4766-7

The sixteen are: C, H, O, N, P, K, S, Ca, Mg, Fe, Mn, B, Cu, Zn, Mo, Cl
Other plants may need: Co, Na, Si, V

All the rest is pure marketing from a fertilizing standpoint. Peat in the lower levels of substrate will rot, causing that axonic region, this is a good thing, also CEC, but tannins as a fert/nutrient.... :?:

Jeff
 

·
Registered
Joined
·
542 Posts
D. Walstad says Humic substances, which sometimes add color to natural waters, make up about 80% of the DOC (disolved organic carbon) in natural freshwaters. For Humic substances she has : Fulvic acid 40%, Humic acid 10%, and Hydrophillic acid 30%. The rest of the DOC (20%) are simple compounds including carbohydrates, carboxylic acids, Amino acids, and Hydrocarbons.

For aquariums the ratios are different. But humic substances help keep micronutrients in solution and available to plants (like iron). It also counteracts metal toxicity because it binds and chelates metals.

I would think the chelators added with iron additives are sufficient. At no time does she mention adding humic substances to an aquarium.

Don't use it like snake oil. Only add to your aquarium what you know is needed.

Steve Pituch
 
1 - 8 of 8 Posts
Top