main source of micro-organism pollution is the biofilm
present in the water distribution system. The only way
to address and eliminate microbial contamination
through the irrigation system is to strip the biofilm
and prevent its re-growth by killing the
Micro-organisms in biofilm are very aggressive and
resistant and form a continuous source of
contamination for plants (y. Pachepsky; J. Morrow; A.
Guber; D. Shelton; R. Rowland; G. Davies; 2012).
Sessile bacteria in biofilms are 10 to 1000 times more
resistant to disinfectants than 'free swimming'
planktonic bacteria of the same species.
When a pathogenic cell switches to the sessile biofilm mode
of growth, it undergoes a phenotypic shift in behaviour in
which large suites of genes are differentially regulated,
resulting in a far more infectious and virulent microbe than
it was in the planktonic waterborne state.
Dispersal of cells from the biofilm colony is an essential
stage of the biofilm life cycle. Dispersal enables biofilms
to spread and colonise new surfaces and infect the soil and
Image Credit: From "Looking for Chinks in the Armor
of Bacterial Biofilms" Monroe D PLoS Biology Vol. 5, No.
11, doi:10.1371/journal.pbio.0050307 via Wikimedia
AQUAZA biofilm control
The Aquaza OXY 300 process is a new generation in irrigation
system cleaning. The controlled oxidization process will
eliminate practically all built up encrustations, bacteria,
slime, algae and mineral deposits in a way which is time
efficient, ecologically harmless, safe on materials and which
does not harm operating personnel.
The Aquaza process is unlike other chemical treatments since it
is entirely environmentally friendly, yet uses powerful products
giving thorough results. Furthermore, accidental spillage will
not damage the soil or plants.
Cleaning of irrigation systems results in higher water quality
and increased flow rate of water and plant nutrition. Treatment
of biofilm with Aquaza involves two steps:
1.) Shock treatment is
used to clean the system of existing biofilms and
micro-organisms in one rapid treatment (occasionally it may be
necessary to repeat the treatment, but in practice this only
happens 1-2 times out of 100, the reason being the type of
biofilm in the system).
Generally shock treatment with Aquaza occurs at the end of a
crop cycle, but can be done during the growing season. The
treatment involves flooding a 0.5 - 2% Aquaza solution into the
water system and leaving this in the system for a certain time
- %/ppm/per m3
5 000 - 20 000 ppm 5 - 20 L per m3
hrs - 30 min
depending on level of fouling
2 000 - 5 000 ppm 2 - 5 L per m3
hrs repeat if necessary
After treatment the system is flushed with water containing 50 -
500 ppm Aquaza until the whole volume of the system has been
flushed 1-2 times and the water runs clear.
Dosage is used to treat water and control biofilm on a
continuous basis. Over and above pathogen and biofilm
elimination, Aquaza adds oxygen to the water - Oxygation.
Oxygation is the science of adding Oxygen to irrigation water
in order to change the growing environment from anaerobic to
aerobic and thus improve plant health and growth.
When Aquaza OXY 300 is dosed continuously at between 20 - 50 ppm
in the irrigation water, due to its unique form of stability it
brings the following advantages to horticulture and
1.) Pathogen & Chlorine elimination in irrigation water
2.) Biofilm eradication in irrigation
3.) Increased depth of pathogen free
aerobic root environment
4.) Enhanced success and rooting of
grafts and cuttings during propagation
5.) Reduction of plant stress due to
under watering, re-planting, excess salinity &
6.) Enhancement of plant immune system
and response to pathogenic infection
7.) Increased vascular systems leading to
increased water and nutrient uptake
8.) Quicker and increased vegetative
(biomass) and regenerative growth (harvest yield)
How it works
Aquaza OXY 300 uses molecular encapsulation technology to deliver
and selectively release Oxygen from a Food Grade Hydrogen peroxide
carrier. OXY 300 Hydrogen peroxide molecules are encapsulated in a
way that selectively controls the decomposition of the H2O2
into water and Oxygen.
The controlled reactivity of Aquaza OXY 300 allows for accurate
dosing and efficient efficacy at extremely low ppm dilutions. The
usual chain reaction decomposition of Hydrogen peroxide is
severely limited by the encapsulation technology, resulting in no
phyto-toxic burn effect and maximum use of each and every
available Oxygen atom.
Aquaza has a long lasting effect as only the necessary amount of
Oxygen to neutralize the Biological Oxygen Demand is released, the
balance of the Hydrogen peroxide remains “On Guard” until more
organic pollution is encountered.
The above test was conducted by one of South Africa's leading
forestry companies to show in decomposition of regular H2O2
and Aquaza through a greenhouse irrigation system. 20 meters from
the point of dosing in the tank, the 100 ppm regular H2O2
has decomposed to a residual of 20 ppm compared to the Aquaza OXY
300 which has hardly decomposed at all. This was done on a clean
irrigation system and measurements were done with peroxide test