Advanced Nutrients and The High P Myth Myth – Dubious Marketing in LALA Land



Author’s note: The material covered herein should not reflect on the quality of the Advanced Nutrients™ product range. The following material was posted on due to the importance of the North American med marijuana movement and the contaminants in med marijuana controversy that recently made press in the US surrounding LA based med dispensaries.





Phosphorous Up in Smoke -Advanced Nutrients™ … Dubious Marketing in LaLa Land


I was recently given a copy of an advertisement by a Humboldt County based Med (215) grower that Advanced Nutrients (AN) was running in High Times magazine.


According to Advanced Nutrients™, high phosphorous levels (among other things) in hydroponic nutrients (namely their competitors nutrients) were the major cause of chemically tasting cannabis.


The Ad followed some controversy and media hype- in the US regarding pesticide contaminated cannabis that was, allegedly, being sold through licensed LA Med cannabis dispensaries. It was therefore an important subject given that negative press had surrounded an already controversial issue of State sanctioned med cannabis and less than ideal growing practices were fuelling negative press. Now it seemed Advanced Nutrients were providing the answer to med users via an advertisement that looked somewhat (very much) like an official medical warning. The answer of course, based on ANs marketing, was that med users should ask their dispensary whether their medicine was grown using Advanced Nutrients.


To quote aspects of the advertisement (not necessarily in the order that the material originally featured):




Med Pot Warning: What Are You Really Smoking?


Your Only Clean Safe Source For Pure Grown Medicine


As the only hydroponics nutrients company founder who is also an officially-government licensed medical cannabis patient and grower, Yordanov pledges his solemn duty to guarantee Advanced Nutrients produces clean, convenient, yield-boosting formulas that ensure patients health and safety.


“I want the finest medicine for myself and all patients. Whether you purchase from a medical cannabis dispensary or grow your own, clearly this is so important to your health that you should insist your buds were grown with hydroponics nutrients designed and tested specifically for medical cannabis.”


Ask If Your Dispensary Medicine Was Grown With Advanced Nutrients…


Because you want your buds to taste great, and you want your buds grown with fertilizers that contain superior sources of phosphorus and contain top quality, analyzed ingredients that don’t contain any poor quality filler.


Because you want your buds to have the highest potency genetically possible and grown with the correct fertilizer ratios of macro and micronutrients.


Because you want the safest, smoothest smoke and the quality of your health demands it.


[End Quote]


And more.




Nutrient Companies Are Harming You


And to make matters worse, nutrient companies are overproviding phosphorus in hydroponic bloom fertilizers. And to compound problems, they use high levels of ingredients like mono ammonium phosphate (MAP) or diammonium phosphate (DAP). These harshness culprits will make you cough a lung out. Really, it’s that bad. Hey, I realize this may sound a bit self serving but obviously I care about what patients and I are smoking and of course the facts are the facts.


The good news is Yordanov’s researchers found combinations of specialized nutrients, plant and mineral extracts, root enhancers, vitamins, inoculants, growth and bloom co-factors that consistently produce bigger yields, higher amounts of THC, sweeter smelling aromatic compounds and tastier smoother smoking buds. In fact, when Advanced Nutrients formulas were tested by Dr. Mahmoud A. ElSohly, (Director of the US government’s marijuana research farm at the University ofMississippi), ElSohly discovered that Advanced Nutrients increased THC percentages by 40% while increasing plant and bud biomass by 21% compared to the formulations he was using. In the interest of full disclosure, Dr ElSohly is now an Advanced Nutrients customer. And Yordanov requires his company’s scientists and quality control technicians to continually upgrade formulations to produce the absolute maximum bud weight and quality.


[End Quote]


Advanced Nutrients have a reputation for sledging their competition but the nutrient “Companies are Harming You” claim was a new high in aggressive marketing tactics on the part of AN. Not only were their competitors nutrients inferior (according to their marketing which states, among other things, their competitors formulas are developed for tomatoes and cucumbers) but also (now) their competitors nutrients were harming med users.


Other than this, Advanced Nutrients spoke of contaminants (the “cut”) in fertilizers. The “cut” being very interesting and colourful terminology that I am sure will offend more than one component fertilizer manufacturer. To quote:



One of the main causes of all that hacking and coughing is plants are grown with too much phosphorus. Another critical finding that made a significant difference was the particular forms of phosphorus and nutrient ratios used to grow with. Even more troubling, what are the rest of the fertilizers essential ingredients cut with? Take calcium nitrate for instance it’s made up of 15.5% nitrogen and 11% calcium, so what’s the other 73.5% made out of? Well, as it turns out, actually it matters a lot, especially the composition and purity level of that cut. When calcium nitrate is not analyzed or sourced incorrectly, the remaining percentage of filler material slows crop growth and adds harshness to your buds. And calcium nitrate is just one example – what about all the other ingredients in a nutrient? Obviously it all matters. But here’s the most important part… the correct ratios of a cannabis fertilizers macro and micro nutrients make a huge difference in your medicines smoothness. Plus it’s a known fact that the further you move away from feeding cannabis plants their ideal nutrient ratios, potency and yield rapidly deteriorate. You see, cannabis uses a small amount of phosphorus during flowering, what it really loves to use is nitrogen and potassium. We discovered this because our scientists have taken thousands of weekly tissue samples from buds, stems, leaves and roots of many varieties using gas chromatography analysis throughout all phases of cannabis growth.


[End Quote]


Author’s note: AN speaks of calcium nitrate being 11% calcium and 15.5% nitrogen but in reality component fertilizers (e.g. calcium nitrate) come with varying elemental percentages. I.e. there is no one/single calcium nitrate product and all component fertilizers based on brand, manufacturer and for that matter- batch-to-batch variations differ in elemental percentages and levels of contaminants. In fact, an 11% Ca and 15% N calcium nitrate component fertiliser represents an unusual product (higher N to Ca ratio which I haven’t encountered before) with less than impressive purity numbers (for instance, a Chinese product I have worked with in the past is 16.6% Ca, 11.76% N or an Israeli calcium nitrate product I work with is 19% Ca, 15.5% N, or a Yarra product I have used is 19% Ca and 15.5% N or yet another product I work with is 17% Ca, 11.9% N and so on. In all cases you will note there is higher levels of Ca to N, which makes ANs quoted Ca (lower than N) and N (higher than Ca) percentages in their calcium nitrate product interesting and somewhat unimpressive when considering fertilizer purities).


As for contaminants….


There is contamination of all kinds in the chemicals unless you are using analytical grade or pharmaceutical grade chemicals and even then there are minute amounts of contamination. Even when using the same brand of fertilizers you will get contamination variances between batches. For instance, the same brand potassium nitrate product on a batch-to-batch basis may be slightly higher in contaminants between one batch certificate of analysis and another. The molar ratio is usually not perfect and will vary from batch to batch.


Let’s throw in a couple of fertilizers batch analyses to look at these contaminants.


Spec on Magnesium Sulphate

Appearance: white/colourless crystals conforms
Purity, MgSO4.7H2O (%) min 99.5
MgSO4 (%) min 47.8
pH, 5% solution w/v 6.0 – 8.0
Iron, Fe (%) max 0.001
Chloride, Cl (%) max 0.015
Heavy metals, Pb (%) max 0.0008
Arsenic, As (%) max 0.0002
S content (%) min 12.9
Mg (%) min 9.7
Size (mm) ~0.2 – 3 –
Cadmium (ppm) ~max 2 –
Nickel (ppm) ~max 3 –
Selenium (ppm) ~max 3 –
Hg (ppm) ~max 1 –


Spec on Calcium Nitrate


Appearance : colourless transparent
crystalline powder –
Insoluble matter (%) max 0.01
Heavy metal (%) max 0.001
Sulphates (%) max 0.03
Iron (%) max 0.002
Chloride (%) max 0.005
Nitrogen (%) min 11.76
Calcium (%) min 16.78

* Ammonium nil
* Particle size (mm) 1 – 3
* Bulk density (g/cm3) 1.02
pH value 5.0 – 7.0
Assay (%) min 99.0
* Nickel, Ni (ppm) ~7.0 – 8.0 –
* Tin, Sn, (ppm) ~7.0 – 8.0 –
* Titanium, Ti (ppm) ~7.0 – 8.0 –
* Typical values not always tested.


The chem theory – just off the top of my head¦. (Avoid this material if technophobic)


1 Mole is a constant number of atoms or molecules which is Avogadro’s No. or constant which is 6.022 something X 1023. This number = 1M or 1mole or 1mol-1. The number actually comes from the number of atoms in exactly 12 grams of Carbon12.


So you can have 1 mole of sodium atoms or 1 mole of sodium chloride molecules which is exactly the same number. So molar ratios are like this. The formula for NaCl (sodium chloride) is in equal ratio 1 atom of Na and 1 atom of Cl so one mole of NaCl would be 1M of Na + 1M of Cl Which = 1 mole of sodium chloride. Or Calcium Chloride which is CaCl2 so the ratio is 1 Ca atom to 2 Cl atoms or 1:2. So to make one mole of calcium chloride you need 1 mole of Ca and 2 mole of Cl ions. The atomic weight of an atom or the molecular weight of a molecule is the weight of 6.022 X 1023 (1M) of atoms or molecules.


Now back to where we were when the product is say potassium nitrate. The molar ratio of atoms making up the potassium nitrate may be slightly out because of some extra free ions of one or the other or it may still contain some of the reactants that it was produced from which haven’t reacted completely or 2 products may be formed from the reaction and it is contaminated from one of the by-products. So usually there are two products being formed or the reaction is an equilibrium reaction.CaCO3 + 2HCl ? CaCl2 + H2O + CO2?


This reaction gives water and carbon dioxide as the by products 2NaCl + CaCO3 ? Na2CO3 + CaCl2


This reaction used to produce calcium chloride as well has sodium carbonate as a by-product; therefore, it could easily be contaminated with sodium carbonate.


CH4 + H2O <–> CO + 3H2


This reaction is an equilibrium reaction i.e. it is a reversible reaction. So the products formed on both sides will be balanced or in equilibrium. If you remove products from the right more of the products on the left will react to form products on the right to keep it in equilibrium.


Chemically confused?? Yes, so is AN.


Let’s simplify this a bit.

The vast majority of hydroponic nutrient and additive manufacturers use only standard agricultural grade chemicals in production. This applies to both hydroponic sector and agricultural sector manufacturers. Due to this, there are invariably contaminants in off the shelf hydroponic nutrients and additives and in solid (dry) agricultural fertilisers. The degree/level of the contaminants will vary dependent on the quality of the component fertilisers used in production and the levels of contaminants in these fertilisers. For instance, if we were to work with only tech grade and/or pharmaceutical grade products we would invariably have far less contaminants (minute amounts) then if we were working with agricultural grade fertilisers.


Rule: The higher the grade of fertiliser used in production (e.g. tech grade versus agricultural grade versus pharmaceutical grade) the less contaminants theoretically- you will have. This equates to a more pure (cleaner) nutrient.

The next thing that needs to be addressed is that some hydro industry manufacturers make claims about their products containing pharmaceutical grade elements. While these claims may, in part, be true, having lab analysed a few of these products (and having received some of the manufacturer direct formulas where pharmaceutical grade elements have been used) it was clear that the bulk (99.5% or more) of the nutrient was formulated using standard agricultural grade fertilisers and in some cases, where we did find pharmaceutical grade elements, they were used at such low levels that their benefits if any- were questionable. For instance, Advanced Nutrients incorporates amino proteinates into several of their formulations (including Sensi Grow and Bloom); something that the company markets off with claims such as Sensi Bloom contains pharmaceutical grade source materials and is manufactured with relentless quality control inspection so your plants get all they need to produce huge harvests.

Very impressive! However let’s have a look at ANs amino proteinate numbers (based on formulas that at one time were used in production in Australia).

(Elemental percentages of micro proteinates removed for website viewing)

MICRO PROTEINATE MIX 28.375kg BATCH                                  /1000L

Iron Proteinate (Fe)                                    10kg                      529g/1000L
Manganese Proteinate (Mn)                         10kg                      529g/1000L
Zinc Proteinate (Zn)                                    5kg                        264g/1000L
Copper Proteinate (Cu)                              250g                        13g/1000L
Boron Proteinate (B)                                    3kg                        159g/1000L
Molybdenum Proteinate (Mo)                     125g                         6.6g/1000L


To touch on amino proteinate theory.

Amino acids are a natural compound that plants produce to solublize and translocate minerals. Plants manufacture these compounds to make minerals biologically available in the cell.
Amino proteinates are organic amino acids (typically glycine) bonded to a micro nutrient ion (e.g. Fe, Zn, Cu).

Micro nutrients in proteinate form have a very stable structure. They can be easily absorbed by plants and directly join the biochemical processes in the plant.

Different fertilisers may contain plant nutrients in different forms, but this doesn’t necessarily mean that plants can absorb one form of an element as easily as others. This idea is particularly true for micronutrients such as iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu).

Proteinate contain plant nutrients as amino acid chelates which are more effective than other forms of nutrients; therefore, proteinates make very effective fertilisers. They are mostly used for foliar application; however, they can also be used for soil application especially in greenhouse vegetable farming and proteinates are suitable for use in irrigation water (i.e. hydroponics).

From a scientific perspective, 2 mole of amino acid to 1 mole of metal (micro element) ion is the ideal to enable optimum nutrient uptake (availability) and translocation within the plant. That is, it requires 2 moles of amino acid to 1 mole of metal ion to effectively chelate the metal (micronutrient) ion and make it more bioavailable than it would be as a micro EDTA (synthetic amino acid) chelate (put simply).

The Micro Proteinate Mix numbers that we have looked at (g/1000L at right of column) represent the amino proteinates that were used in a 1000L batch of AN Sensi Bloom and AN Sensi Grow in ANs Australian formulations. There is a total proteinate weight of 1500.6grams or approx (just over) 1.5kg in a 1000L batch of nutrient. Let’s say, hypothetically, that the 1000L batch of water and mineral elements (component fertilizers + water) weighs 1400kg; What we are then left with is a nutrient that contains approximately 0.108% of microproteinates the rest of the formulation (approx 99.892%) being made up of standard agricultural grade fertilizers and water. Looking at this another way, based on the Australian Sensi Bloom formulation (or at least the formula I have) the total mineral (MAP, MKP, calcium nitrate, urea, potassium nitrate etc) equates to 558.5kg of component fertilizers in a total 1000 litre batch (with 110kg of this being derived from MKP monopotassium phosphate- and MAP mono ammonium phosphate-) with 1.5kg of the total component fertilizer weight, used in production, being micro proteinates. That is, 1.5kg of amino proteinates in a total of 558.5kg of mineral elements equates to 0.27% of the total mineral weight used in the production of 1000 litres of Sensi Grow and Bloom. When you put up these numbers things become somewhat clearer beyond the marketing jargon.

The bottom line:  It sounds impressive from a marketing perspective to claim the use of pharmaceutical grade elements or micro proteinates in nutrients and additives (and certainly at least two companies are more than aware of this); however, AN are using amino proteinates at extremely low levels (for instance, AN add much higher levels of Fe as EDTA and DPTA, Zn as EDTA, and Cu as EDTA to the same formulations) and because of this any benefits gained from the use of amino proteinates  – if any- are open to question (at least from a scientific/theoretical perspective).

I could break this down further but amino proteinates are not the center of discussion. The issue is phosphorous (according to Advanced Nutrients) and contaminants in fertilizers. More importantly, the issue is ANs credibility in advertising. I.e. How reliable/credible is this company with the information that they provide to the consumer? After all, they have launched out with an Ad campaign, arguably, marketing off a controversial subject – geared towards the medicinal marijuana community with claims of:


  • Increased THC percentages by 40%”
  • Increased plant and bud biomass by 21%”
  • Combinations of specialized nutrients, plant and mineral extracts, root enhancers, vitamins, inoculants, growth and bloom co-factors that consistently produce bigger yields, higher amounts of THC, sweeter smelling aromatic compounds and tastier smoother smoking buds
  • And most importantly, where med users and growers are concerned using AN nutrients will counter problems of chem tasting and contaminated cannabis that will make you “cough a lung out”; that is, AN Nutrients are the answer to the recent media controversy surrounding Med cannabis (or presumably this is what they’re pitching)

This type of marketing could be influential and it is important that it is dissected on a scientific/chemical level. I.e. Are AN nutrients the answer to non contaminated cannabis or are AN leading med growers and users up the garden path.
Before we move on, I’m going to cut and paste in an excerpt from the book I’m currently penning. I’ll come back to ANs most recent claims in a moment. Let’s establish the premise first.  This excerpt follows a chemical analysis of a manufacturer direct Dutch PK 13-14 formula that is provided in my new book (Integral Hydroponics, Nutrient and Additive Production for the Home Growers -.coming soon). In the analysis of a Dutch PK 13-14 formula I establish that PK 13-14 (listed under US standards of P as P2O5 and K as K2O) is actually elemental PK 5.67- 11.6 or roughly double the K to P ratio). That is, the phosphorous in elemental PK 5.67 – 11.6 = 5.67 (%w/v elemental P) x 2 = 11.34 (%w/v elemental K) and we have a PK product of 5.67- 11.6 or just (marginally) over double the K to P ratio. Hold that thought for a moment.


Next – keep in mind that some countries (e.g. America) list P as P2O5 and K as K2O %w/v so sometimes manufacturers list with elemental numbers while in other cases these numbers (listed as P as P2O5 and K as K2O) appear much higher.


Phosphorous as P2O5 is only 43% elemental phosphorous and potassium as K2O is only 83% elemental potassium. Therefore, if a product is listed under North American standards as PK 13-14 it is actually: P = 13 (%w/v as P2O5) x 0.43 (% elemental P in P2O5) = 5.59 (%w/v elemental P) and K = 14 (%w/v as K2O) x 0.83 (83% elemental K in K2O) = 11.62 (%w/v elemental K) = PK 5.59- 11.62.


After looking at the numbers and the formulation of the Dutch PK 13-14 product I pick up on some Advanced Nutrients marketing material surrounding their Hammerhead™ PK additive.


To quote myself:




I’m going to deviate for a moment (take a breather from the heady world of chemistry) and point out some industry jargon to reinforce an important point (the moral to the story).

Recently I received an original potash formula (manufacturer direct), which a large multinational North American company used in production in Australia.

I looked at the formula and considered it nothing special (perhaps better than some – no better than others and based on my personal views not as good as a few formulas I’ve looked at – or at least at first sight).

I then went to this company’s website to see what bells and whistles (jingoism) they had surrounding their product.


Ha! Ha! Ha! I thought. That’s odd what a load of nonsense!


What the company’s promotional material had to say about the product (among other things) was the ratio of PK 13-14 (in European formulations) was incorrect and that a well balanced potash formula should have double the K to P ratio; therefore, their formula had double the ratio of K to P and, therefore, it was superior to European  PK 13-14 products (which are, based on our European PK 13-14 formula, in fact PK 5.6 – 11.6 or roughly double the elemental K to P ratio that this company was promoting as the right P to K ratio, if you see my point).


Actually, here’s what Advanced Nutrients had to say.



The problem starts with the fact that most PK formulas available on hydroponics store shelves are PK 13-14 bud stimulator formulas (the numbers 13 and 14 refer to the amount and ratio of phosphorus and potassium in a bud booster).

PK 13-14 Is An Old, Ineffective PK Ratio Appropriate Only for Outdoor Farming Crops… Not the Kind of Crops You Grow Indoors

You might ask yourself: if PK 13-14 formulas are so bad, why do they dominate the marketplace?

The reason is almost all hydroponics manufacturers and hydroponics stores offer PK 13-14 formulas, and until now, unfortunately that’s pretty much all you’ve had available when you wanted to add PK to your bloom phase nutrients.
Too bad the 13-14 ratio has been so pervasive in the market place of general hydroponics supplies. Fact is, the 13-14 ratio isn’t the ratio that your specific types of plants need for producing bigger yields.

Instead, the 13-14 phosphorus/potassium ratio is based on field crop agricultural research that’s many decades old and totally inappropriate for your hydroponics gardening plants.

The 13-14 ratio was created because phosphorus leaches out of soil quickly, especially when orchards and field crops are irrigated.

When hydroponics indoor gardening started to demand bloom boosters, most hydroponics nutrients companies took the lazy way when they decided how to make a bloom booster..

All they did was just adopt the 13-14 ratio that only works for outdoor ag field crops like corn and soybeans.
Fortunately, now there’s been a breakthrough in scientific research that reveals the ideal PK ratio for your high-value crops. Here’s a hint: it’s not PK 13-14!

The startling realization comes when you notice all but one PK bloom booster have virtually equal amounts of phosphorus and potassium. This isn’t the right balance of PK for your plants.” (Author’s note: Keep in mind that we have already established that PK 13-14 is actually PK 5.67- 11.6 or double the K to P ratio)

“The good news is there’s one PK bloom booster that contains the correct ratio and type of phosphorus and potassium: Advanced Nutrients Hammerhead PK 9-18


Are we getting anything from this yet?


What was clear was that this company either knew very little about chemistry or they were proliferating misinformation (arguably via subversive marketing) regarding their competitors products.


Next, AN listed their Hammerhead™ product as PK 9-18. This of course would make it, according to US standards (given that they are a North American company), PK 3.87 -14.94 and that certainly is way more than double the K to P ratio that they promote, at least according to US standards of listing P as P2O5 and K as K2O. However, from this I then took (perhaps incorrectly) that they couldn’t be listing their product in line with North American standards. Unusual, given they are a North American company but who am I to argue? OK, so maybe, they’re listing it as elemental PK 9-18 I thought. Or maybe they were trying to say double the K20 to P2O5 ratio – who knows!!!


Next, I went to the North American manufacturer’s Australian PK (potash) formulation and calculated the elemental P to K ratios that the formula contained.


Without going into yet more mathematical equations (we simply don’t need to), what I came up with was that in a 1000L batch of their formulation, there was 59.88Kg of elemental K and 41.125Kg of elemental P (or elemental PK 6- 4.1 or under US standards of listing P as P2O5 and K as K2O PK 14- 5).


That’s right!! Nowhere near double the K to P ratio AN was promoting as optimum (while criticizing/sledging their European competition who according to ANs own jargon – seemingly had got it right, while AN had seemingly got it wrong, if you take my point.


I could break this down further to ppm (% w/v) but why bother? Their formula (or, at least, their Australian formulation) is miles out.


The moral of the story… I’ll let you decide. 


[End Quote]


Let’s look at a lab analysis of Sensi Bloom. The lab analysis was conducted in Australia in 2005 (on an imported product) and it is possible that the formula has changed somewhat or may differ on a country-to-country basis. We’re awaiting a new lab analysis from the US on Sensi Bloom and ANs Connoisseur range (given the advertising was targeted towards the US market) and will post this data shortly (View US Lab Analysis conducted 2010 – new material).















NH4N (mg/L)



NOXN (mg/L)



S (mg/L)



P (mg/L)



K (mg/L)



Na (mg/L)



Ca (mg/L)



Mg (mg/L)



Cu (mg/L)


< 0.5

Zn (mg/L)



Mn (mg/L)



Fe (mg/L)



B (mg/L)



Cl (mg/L)






COND. (dS/m)




Sensi Bloom, in this instance, has an elemental NPK %w/v ratio of 8.8- 2.7- 7.78 with Ca of 1.1.


I found this analysis interesting. AN uses high levels of urea (NH2)2CO in both their Sensi Grow and Bloom products. Firstly, urea is the cheapest source of N. Other than this, urea use in hydroponic nutrient formulations is typically avoided due to slower absorption (particularly in early growth), translocation and assimilation of urea to that of other nitrates (such as NO3 N) in hydroponic systems. However, recent research seems to suggest that urea, in hydroponic tomato crops, is a suitable source of N and that its translocation is improved during the latter stages of growth. This aside, most hydro nutrient and agricultural premixed fertilizer manufacturers (e.g. Scotts Co, USA and Haifa, Israel) do not use urea in hydroponic tailored formulations (e.g. Scotts Co Peters Hydro-Sol/Combi-Sol contains 5% N as NO3 and Haifa Polyfeed contains 6% N as NO3).


Author’s note: Use of a brand name does not constitute an endorsement.


Briefly about nitrogen (N) in hydroponics.


There are two commonly found types of nitrogen (N) in hydroponic nutrient concentrates. When you look at a lab analysis of a hydroponic nutrient you will typically see something like this:


NH4N (mg/L)


NO3N (mg/L)



NH4 N refers to ammonium nitrogen and NO3 N refers to Nitrate N. NO3 N is more suitable than NH4 N in hydroponic fertilisers. NO3 N is available immediately to plants while ammonium N (NH4 N) becomes available more slowly.


NO3 N is derived from the nitrate fertilisers (e.g. calcium nitrate, magnesium nitrate, potassium nitrate), while NH4 N (ammonium N) is derived from the ammonium fertilisers such as ammonium nitrate, ammonium sulfate, monoammonium phosphate etc.


Urea (NH2)2CO is another form of water soluble nitrogen.


(NH2)2CO (Urea) is completely different from ammonium and nitrate nitrogen. Basically, before urea (a chemically organic nitrogen) becomes available to the plant it first must be converted into inorganic ammonia N (NH4+). Actually, that’s perhaps over simplified because recent research also shows that urea is directly uptaken by plants but let’s not get too technical. Basically, a lot of urea in hydroponic solutions becomes ammonium nitrogen….


Another interesting factor is AN Sensi Bloom contains (comparatively to many other nutrient brands) extremely low levels of calcium, indicating that low levels of calcium nitrate (comparatively to most other brands) have been used in formulation. Perhaps this is why they note calcium nitrate (albeit perhaps mixing up the numbers) in their advertising (re contaminants) but let’s not get too excited about this – all component fertilizers (e.g. urea, potassium nitrate, magnesium nitrate, MAP, MKP) contain contaminants and low levels of calcium nitrate in a nutrient tells us very little about the overall levels of contaminants in a given fertiliser (in fact phosphorous containing fertilizers – as AN point out – are far more of an issue than Ca fertilizer).


Other than this (more importantly), Sensi Bloom, based on the lab analysis, contains about the expected or thereabouts- levels of phosphorous that you would expect to find in a standard bloom nutrient. So far nothing unusual or unexpected about phosphorous.


Now let’s compare Sensi Bloom to a multi national “crop specific” European bloom formula (lab analysis) to demonstrate the point.
















NH4N (mg/L)



NO3N (mg/L)



S (mg/L)



P (mg/L)



K (mg/L)



Na (mg/L)



Ca (mg/L)



Mg (mg/L)



Cu (mg/L)



Zn (mg/L)



Mn (mg/L)



Fe (mg/L)



B (mg/L)

< 0.5


Cl (mg/L)






COND. (dS/m)




NPK %w/v 5.58- 1.7- 6.3. Ca = 3.342


When comparing the NPK numbers of formulas, dilution rates (concentration) need to be factored into the equation. In this case, the Sensi Bloom is a more concentrated formula than the European product and this reflects in the numbers. However, the AN Sensi bloom product has 3.3%w/v more N, 1%w/v more P and 1.48%w/v more K so overall the NPK numbers are very different (Sensi Bloom is arguably heavy on N and about the same on P when dilution factors are considered- as it’s European competitor). Other than this, compare the calcium (Ca) %w/v numbers. The AN formula has less than half the Ca %w/v (while being more concentrated) than that of the European formula… Quite simply, they are extremely different looking products/formulations and yet both companies claim to have conducted extensive crop specific research. (Odd??)


Of course, the next thing we need to consider is ANs extensive feed chart (recommended feed regime or feed calendar) that requires/recommends the use of numerous (13) AN additives (including the P and K boosters “Bud Blood, Big Bud and Overdrive- during bloom) in conjunction with their Sensi nutrients. Of course, according to Advanced Nutrients, these additives are required to realize optimum yields (near genetic potential) and all of the AN additives come at an additional cost.


Ok let’s consider the European company’s feed chart first. The European company produces a PK 13- 14 (theoretically, elemental PK 5.67- 11.6) additive that they recommend should be used at 1 – 1.5ml/L for 1 week only in week 3 of flower. What this tells us is that by using this company’s recommended PK booster and nutrient regime (boosting existing P and K levels in the overall NPK at week 3 of flower) we are adding, based on a dilution rate of 1ml/L,  approximately 567ppm of P (56,700ppm P in PK 13- 14 concentrate divided by 1000) and approx 1106ppm of K to the nutrient (feed) for one week at week three of flower. Without conducting tissue analysis we can only speculate as to what this means in terms of residual phosphorous levels in the crop (at harvest) but what I can safely say is that the use of additional phosphorous, in this instance, is minimal (when comparing some other companies including ANs- P and K additive recommendations).


Now to Advanced Nutrients who go in an entirely different direction with their recommended feed regime.


Firstly, they recommend using Bud Blood in week 1 of flower. Bud Blood has an NPK ratio of 0-39-25, which, assuming it is listed under US standards, is elemental NPK 0- 16.77- 20.75 (in both listing scenarios, not double the K to P ratio that AN promote as the ideal in PK ratios). However, here’s where things get interesting. Advanced Nutrients then recommends using Big Bud (NPK 0-15-40) from week two to week four and then Overdrive (NPK 1- 5- 4) for week five and six, with week seven (week before harvest) without P and K additives.
AN promote Big Bud™ with:
Web Description:



“When you see an Advanced Nutrients product, you’re seeing a well-researched, intensively-tested formula that nobody else can duplicate. When people want amazing results, they use Big Bud because it contains optimized ratios of Phosphorous, Potassium, Magnesium and Amino Acids that dramatically increase growth, width, weight and resin production. Big Bud will trounce performance of similar products made by other companies, or your money back.”


[End Quote]

Impressive but let’s not forget the dreaded phosphorous! That’s week 1- 4 with additional P and K.


Next AN promote Overdrive for week 5 and 6 with marketing material such as:


“Now you can say goodbye to frustration and hello to bigger harvests. The good news is that there’s a surefire way to beat the odds and make your big harvest dreams come true. The answer: Advanced Nutrients Overdrive. It’s 100% guaranteed to give you rewarding harvests.

That’s because Overdrive contains a unique set of powerful ingredients that stimulate plants to increase their bloom productivity. Overdrive is a really special formula that does something that used to seem impossible. It makes plants go full throttle on flowering, even late in the game.

But now you can use Overdrive to defy Nature and turn your plants back into fire-breathing champion producers, even when they’re well into bloom cycle!

Field testing shows that Overdrive reinvigorates flowering and creates a renewed burst of resins, scents, terpenoids, size and other very desirable traits that will give you impressive harvests instead of disappointing ones.

You know what? It wasn’t easy to create this late-season plant growth miracle formula. Our scientists spent several years examining plant tissue samples and running experiments on the kinds of plants you grow. They also examined the internal clocks that run a plants life cycle.

They discovered a never-before-used combination of vitamins, organic materials, nutrients and other ingredients that make Overdrive a powerhouse harvest-boosting formula used by thousands of growers worldwide.

For example, Overdrive contains special forms of folic acid that work on a genetic level to reprogram blooming plants so they produce larger flowers late in bloom phase.

Overdrive also contains plant-friendly forms of Vitamin C. These special vitamins increase photosynthesis efficiency and makes plants better able to deal with heat, high intensity lighting and stress.

All of Overdrive’s ingredients are matched so they work together to give your plants exactly what they need for late-season bloom building.



OK, Overdrive is certainly impressive gear; full throttle “nature defying flowering”, “fire-breathing champion” and a “powerhouse harvest-boosting formula” with a product that works at a “genetic level”. I’m definitely impressed! So many adjectives attached to a single product.

The only problem is…. More phosphorous.

Overdrive is made using potassium nitrate (K and N), mono magnesium phosphate (Mg and Phosphorous/Phosphate), mono potassium phosphate (K and Phosphorous/Phosphate) and magnesium nitrate (Mg and N), among other things. Actually, here’s the ingredients based on the Australian production formula (g/L deleted for website viewing).

Potassium Nitrate
Mono Magnesium Phosphate
Mono Potassium Phosphate
Magnesium Nitrate
Ascorbic Acid (vit C)
Folic Acid (vit B9)
Fulvic Acid


What this means is that based on Advanced Nutrients feed chart (and based on the phosphorous/phosphate levels in Sensi Bloom, Bud Blood, Big Bud and Overdrive) we are adding higher phosphorous levels for 6 weeks of flower than we otherwise would be using the European producers feed chart and products. I.e. The European producer recommends the use of PK 13- 14 at week 3 for 1 week, which allows several weeks for excess phosphorous (provided by PK 13-14) to clear (i.e. theoretically the additional phosphorous derived from PK 13-14 is used by the plant and converted into biomass).


Advanced Nutrients, on the other hand, advise the use of a phosphorous/phosphate containing product at week 1 of flower and then throughout the next five weeks of flower, meaning that at least some extra phosphorous (on top of what is already in Sensi Bloom) is provided far closer to harvest (or, in some cases, until harvest). To their credit ANs feed chart also allows for a weeks flush at week 7.  I’ll let you do the math on this one – it isn’t rocket science. Which nutrient line (when contextualising additives) contains lower levels of phosphorous?


ANs PK additive feed calendar with Sensi Bloom (per 100L)


Week 1 40grams Bud Blood

Week 2, 3 and 4 Big Bud Powder

32g wk 2, 34g wk 3, 36g wk 4

Wk 5 and 6 Overdrive

200ml wk 5, 160 ml wk6

Wk 7 no PK and no nutrients


(Author’s note: In just about all instances, nutrient manufacturers advise to flush on nutrient calendars and therefore AN don’t differ in this aspect)


The end….