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hydro_esox

For those who use DIY nutrients

hydro_esox
14 years ago

I have had my hydro garden for a couple years growing peppers, tomatoes, cucumbers, pumpkins, and various herbs. I have used Botanicare Pro with really good results.

Now I want to take more control in the whole process to open up the "tweaks" available to me. This area, at least to me, seems to have very sparse, and at times scratchy info. I have seen many recipes for mixing nutes. It doesnt scare me to mix my own and i have already tried finding suppliers for the verious salts.

My questions are:

In Wisconsin we are limited on chem. suppliers. We have many farm coops that can bring in calcium nitrate and such, but are there any you have to order online, if so where do you order?

Also I have read different opinions on what grade to use, for those who make there own nutrients will the coop grades work, or are there certain chems you need to be higher grade?

Has anyone tried to incorpate things like botanicare pure blend pro ie. fish meal, kelp, etc?

I see very few recipes with potash ( had a tabacco farmer give me some and the stuff worked awsome) anyone know why, or am i just not seeing it?

Lastly, im not asking for your "secret blend", but are there any suggestions for a good starting base nute recipe ( It seems many diff recipes use many diff chems, i just wanna get a basic "get my feet wet" with this project recipe)

sorry for the long post, but this forum has been a big help in the past, and I figured you guys could help.

Thanks in advance

Comments (29)

  • lucas_formulas
    14 years ago

    Just a few things you should know before inquiring for components and raw materials, eventually for formulas and recipes: there is a specific and restricted number of suited ingredients. For both macro- and micro elements. Have you got that list? Don't get too creative or fancy with those, this is a known known, and as a matter of facts you can't go far off trail here.

    Right, it's hard to lay hand on specific formulas and you never know how good they actually are and if they'll work for you. Well, I guess it's mainly because of 3 reasons, 1. plants are quite adaptive and can/will grow more or less well with various formulas anyways. 2. There has been quite some research about this topic, but I have found little that you can use or apply directly. 3. The professional growers and manufacturers have got their formulas an recipes but they do not share them like a box of donuts at the office. Also, even if they have got a few formulas often they don't know- or don't really understand why and how they work. Some chemists or scientists may know more of the later, but often they haven't got the time or the passion to test it by themselves "in the field". Well, that's how I believe how it comes - and that's my way of putting it.

    From my own experience and tests I would conclude that plant nutrition and formulas don't necessary need to vary as much as some people might think. It surely is complicated, but much less variable as some dealers or manufacturers would like it to be for their commercial purposes. Simply have a look at nature: does every plant have got their own growing formula and additives, and do they even change a bit with vegetative- flowering or fruiting stage? Not exactly, - right! And yet in hydroponics there are some basic differences with formulas that seem to matter. There is quite some contradiction and some myths (that will probably never die) in this field, as there always are some of those in almost any field you wrap your head around for a little longer.

    You are asking for a basic recipe to "get your feet wet", I understand what you mean and that's fine - but if you'd be more precise with the type of vegetables you'd like to start growing, it would be easier to get you what you need to get started.

    Also, please specify if you'd like to have a formula including ppm of each element (N,P,K, Ca, S, Mg, etc.) or only the recipe that calls for the mentioned ingredients as calcium nitrate, potassium phosphate, magnesium sulphate, etc...?

  • hex2006
    14 years ago

    Hi Hydro
    I initially found it easier to buy a 55lb bag of commercial agricultural hydro nutrient with chelate trace elements to use as a base.
    You can modify it quite easily to fit the bill using additional calcium nitrate (cheap),mag sulfate(cheap) ,potassium nitrate (more expensive),MKP (usually the most expensive). Small amounts of Potassium Sulfate (sulfate of potash)can be useful too.
    Depending on the base, the largest percentage of the additions will be calcium nitrate and mag sulphate, which happen to be the cheapest :)

  • lucas_formulas
    14 years ago

    I believe (from what I read) that many came to settle for some solution of the kind (described by hex2006). I can understand that approach, and I believe it might be an acceptable solution for a lot of people who have settled for that alternative. But than again, I feel like saying or asking: if you are just one step away from being "able" to really make your own nutrients from scratch, without restrictions (that are actually in vigor by this method) why not taking the final step but dealing with that "Caballo Sin Nombre" instead?

    You also have got (need most of) a bunch of ingredients, you have to actually use a scale to weight all components, understand and do the (nearly same) maths, take the same care to not mess the whole batch up, in some case even use 2 component concentrates, etc, etc... what can possibly prevent you from accomplishing the whole mission? ;-)

  • hex2006
    14 years ago

    Hi Lucas,
    Some peeps might be more comfortable with sticking a toe in the water where others are happy to dive in head first ;)
    I don`t use the commercial base method anymore but it was a cheap and easy way to get started and you gain some useful experience with stock solutions, formulating recipes etc.
    I use seperate ingredients now, the initial cash investment for everything can be quite considerable, depending where you live and quantities available.
    The silver lining is most of them you will probably only need to buy once. A 55lb sack of MKP could last forever unless you own a farm :)

  • lucas_formulas
    14 years ago

    I basically agree and I also am pro-pluralism where ever it applies...
    But let me just differentiate somewhat at the end: in case I'll go for that option, I'd chose a SIMPLE and easy solution then. As you said, a bag of some commercial solution plus some pinch of whatever...
    Because, if you'll continue to add one or two more ingredients, and perhaps another, you see where I want to get at, - soon enough you'll be in the water head over heels ;)

  • hex2006
    14 years ago

    Oh yes, thats how i eventually made the transition :)
    You amass a cupboard full of chemicals and concoctions,and suddenly you`re only one or two ingredients short of becoming a master at it lol.

  • hydro_esox
    Original Author
    14 years ago

    Hex: I like the idea of making my own, however your idea may be my only option if I cant find all the chemicals. If this is the case I have a (dumb) question. Could i use a soluable fert that has ten percent nitrogen from urea (I see conflicting reports that its actually bad for the plants(true/false?), or if its that they just cant use the nitrogen without being broken down by soil microorganisms into a usable form, in wich case i could supplement with calcium nitrate?)

    Lucas I would prefer it it in recipe form (grams) to mix together, and ratio of concentrate to water volume for final mix. Since im new i would like to stick just to tomatoes and maintain my peppers with the botanicare I have left.

    Also when i called they had different forms of some of nutes (liquid/granular) (Lingo???/Oxidates??? .... no idea what those mean and i dont have spelling as it was told to me over the phone) i guess i need some clarification here

  • grizzman
    14 years ago

    This is directly from the newbie must have list thread on page 2 (currently);

    I use a soluble hydroponic solution from southerag. Their pdf catalog isHere the product I use is on catalog page 6 at the bottom. you also need greenhouse grade calcium nitrate and epsom salts to complete the mix. I bought the epsom salts at the local pharmacy and the other two I bought from a local landscape supplier. (they ordered it for me)
    Start here for more indepth instruction and component lists for building your own fertilizers.
    Also, Jean-Luc has posted nutrient requirements for several plants here, so just search the forum.
    BTW, I use the premixed soluble hydroponic solution hex mentioned supplemented with calcium nitrate and epsom salts. I believe it costs about $25 for the bag, but shipping might double that.

  • hydro_esox
    Original Author
    14 years ago

    Grizz: im familiar with southern ag as it has been on these forums for quite sometime. Shipping would kill me. And i also have that site bookmarked on my browser for the recipe... along with a couple others (coopers, resh, etc recipes) im just curoius if anyone has found any advantages of one over the other, or if one is easier to obtain the chemicals for or easier to mix?

    The coop had tried to sell me a product simlar to Gainer 20 20 20 ( a soluable fert) but the nitrogen is 10 percent from urea.. i would like to know if the urea is actually toxic in hydro or if i could just add some other sources of nitrogen from nitrates ... ( in wisconsin we have a Hydro rose gardener who uses this mix (gainer 20 20 20) with really good results, i just dont know if for toms the urea woould cause a toxicity?)

    Thanks in advance

  • hex2006
    14 years ago

    Hi Hydro
    I was in the same boat as you, no local suppliers and chelate trace elements only available in sizeable quantities which would`ve bumped the initial outlay cost to silly money. You`ll find yourself adding an odd element to your collection here and there over time. Sooner or later you`ll have the full set.

    Be careful to read the label on the epsom salts, its generally mag sulfate heptohydrate which has less mag and more sulfur than agricultural grade mag sulfate.

    Grizzman is absolutely right about the shipping costs (usually extortionate hehe) but it`ll still work out much cheaper. Buying a bottle of basic tomato feed from a store is perhaps 8-10x more expensive than mixing your own with the same elemental values.

  • hydro_esox
    Original Author
    14 years ago

    I would like to take this time to thank all the regular contributors to this forum as your information and help has proved invaluable.

    I still have many questions and am learning more everyday (i hope)...

    here is a link to a dry mix i am looking at... if someone could evaluate it to see if it would work, im assuming i will have to add calcium nitrate (ammonium sulphate?) and epsom salts to complete it.

    http://www.rsamicrotech.com/pdf/Dry%20Soluble%20Foliar%20Fertilizers/Gainer%20Solubles/Label%20-%20Gainer%206-30-30.pdf

    6 30 30 with micros added and water solubale.

    I believe for this season i will use the dry and add some chems to it.

    I will continue to research making my own from scratch and as the summer continues try to actually do it as i become more comfortable with it. ( It seems i really should have started this last fall to be ready to make my own nutes for spring. Hindsites 20/20)

  • hex2006
    14 years ago

    Hi Hydro,
    The mix looks like ~32% of the total nitrogen is from ammonium. It shouldn`t be a problem as the N is light so additional calcium nitrate would sort that out and the missing calcium component. Magnesium Sulfate sorts the missing Mg and S. (Ca,Mg and S are not listed in the analysis).
    The elemental NPK of the mix based on the analysis (no additions)is 1 - 2.2 - 4.1

  • lucas_formulas
    14 years ago

    hydro_esox,

    I wouldn't recommend this G 6-30-30 as a base. While the ammonium part of the nitrogen isn't a problem, the phosphorus content is way to high in relation to the potassium. Too high P versus K may indeed cause iron and calcium deficiencies. Trace elements are not the ones of a hydroponic solution but those of soil fertilizers. B, Fe, Mg and Zn are indeed very low and with adding more and more components, they get only lower proportionally.

    I'd rather chose a base nutrient that is actually meant to be used, or suited for nutrient solution and has a much lower phosphorus ratio. Phosphorus is anyway overrated in most fertilizers and nutrient formulas for some unknown reason to me.

    PS; you were asking about ammonium sulphate, well this component is rarely used (sparingly) in nutrient formulas. It only will be added if the nitrogen content is only provide by calcium nitrate, to add up to 5-10% more ammoniacal nitrogen in some cases. It also provides a load of sulphur, and you have to add this part to the one that is already provided by magnesium sulphate aka "epsom salts".

  • hydro_esox
    Original Author
    14 years ago

    Thank you hex... one last question, im going to try and find the answer myself after i post this but in case i come up dry (or confused), how do i go about calculating the amount calcium nitrate and magnesium sulfate to make this mix proportionate?

  • hydro_esox
    Original Author
    14 years ago

    Lucas how about this ratio 9-15-36

    I kinda compared this to the SouthernAg (grizz recomended) they seem similar in trace except mine has less boron and molybdenum.

    link below for more details, trace elements seem the same just a different NPK ratio as the previous link i posted.

    http://www.rsamicrotech.com/pdf/Dry%20Soluble%20Foliar%20Fertilizers/Gainer%20Solubles/Label%20-%20Gainer%209-15-36.pdf

    This is the only brand and type of soluable fert available near me that i have found... if it really wont work, guess ill just have to jump in and go for the full recipe from scratch. the same coop can order just about any chemical i need, will be there this saturday to see what else they may have. Until then i have alot of research to do.

    Thank you again

  • lucas_formulas
    14 years ago

    9-15-36 is much better from my understanding , especially if you target
    tomatoes and peppers.

    As for the similarity with the other formula that grizzman uses, I didn't want to interfere at that point, as I do contradict him too often already... and I don't want him to think it's personal or systematic. ;-)

    Seriously with the 9-15-36 the P-K ratio is more balanced and yet P still to high from my understanding. But here you have more flexibility with the amount of N you add versus K. And that's not a personal opinion or preference but a fact that can be confirmed by a second "opinion".

    Here is what I once calculated for a chap who uses Peter's Hydrospl 6-18-36 (+3) with calcium nitrate.

    Mix 1 is without supplementing Mg and Mix 2 with adding Magnesium Sulphate.

    It's a tomato formula leaned on research from the University of Florida that uses less Nitrogen with tomatoes to prevent excessive vegetative growth. The guy has been using it in Tasmania last summer and has had excellent results as far as he has reported back to me.
    If this formula will be used in mild or cool climate, the concentration could be increase by plus 0.1 gr of each. Hydrosol and Calcium Nitrate. 50+ ppm of Mg is enough. It could use even a little more K, but that would raise the Phosphorus in the same time. And that should be avoided to prevent interference with Ca and Fe availability.

    Used units:
    g= gram
    l=liter.

    PS: all ppm are only approximative, because if the manufacturer says 9-15-36 it certainly isn't precise, it could in fact be something like 8.85-14.95-36.1. or similar

  • hex2006
    14 years ago

    Grizzman`s base nutrient (SA Soluble hydroponic Special 5-11-26) is reasonably close to what i used (5.5-16-30 +5Mg) with the exception that some of the SA micro`s are much lower. If you have enough headroom in the micro`s its no real problem to increase P to bring it into line and then dilute the mix.
    Its surprising that a lot of growers fail to include their start water ppm`s and ph down additions which is commonly phosphoric acid :)

  • lucas_formulas
    14 years ago

    You guys don't need to agree with me on the needed P content, or the fact that too high P may affect Fe and Ca availability, besides the fact that the commonly used components to provide P are the most expensive and hence you pay for something that is just in your way ;-)

    But I would think about it if I was you ...

    I don't use these products because I manufacture nutrients from components only. If I would need them, I'd not be happy with the fact that if I wanted to push K content to over 230 ppm, (as in 250-320) the Phosphorus content would obviously get into my way. Btw: 23-28 ppm of Phosphorus is actually sufficient to optimal, even if that isn't commonly spread or accepted by most. Ask professional growers if they truly add 50, 60 or more ppm of Phosphorus to their solution or if they prefer save that money.

    About PH, I don't use any auxiliary acids or PH downs, I calculate and compose my nutrients in order to fit and buffer my base water PH-vise in the first place. As for water start ppm, I fortunately have very pure, nearly calcium and mineral free water. Hence I don't fail to include any of it, I guess. ;-)

  • grizzman
    14 years ago


    Jean-Luc,
    I don't mind if you contradict me. I'll even overlook your petty jab above. We all come at this from different perspectives. You might note most of our arguments have nothing to do with your replies to my comments.But that is neither here nor there since we're somewhat in agreement on this thread.topic>
    The difficulty you come into with what I use is that to keep the calcium in the range of 100 ppm, you can't get the ratio of p:n above about .48 and that's pushing it. 0.4 is usually what I have to settle with. I may look into getting some phosphoric acid to help with that this year. Also, although the micros may be less than peters ( I don't know, but assume hex has looked), the only one that is outside the minimums for my general solution is Iron. I don't concern myself with that because I know there is iron in my well water. The red rind around my sink drains tells me that.


  • lucas_formulas
    14 years ago


    I keep it brief to not interrupt the topic. Not sure what a "petty jab" is, but what I wrote earlier was meant to be ironically informative. Actually I wanted to sound nice for a change, not sure if I succeeded with that ;-) Btw: I am glad about more and more frequent agreement lately.

    But as for the Phosphorus I didn't mean that it would come too short, but in excess as soon as you want to increase the Potassium content without using supplementary components as potassium sulphate. And as I told you earlier 100 ppm of calcium (in your case) in the formula is fair, especially if some extra is provide by well water. Iron deficiency should show up in case it would be short, I mean you should have noticed it since.

    But for others the low Fe content in these products may turn out to become an issue, that's why I actually mentioned it. And don't forget that you running a low concentration strategy, others might push that part a bit and really would have Phosphorus in excess then.

  • hex2006
    14 years ago

    I guess its all relative to the goals you set.
    The dry mix may contain more of the expensive elements than needed, but its still more economical than buying a commercial nutrient in a bottle (which incidently, generally sport excessive levels of P and K)and,in the short term at least, buying seperate ingredients in bulk.

  • lucas_formulas
    14 years ago

    Of course, that the economic argument (in comparison to liquid/bottled nutrients) is valid here, but that's not covering for the limits you may sign for by the choice of your base nutrient.

    What is true for the Phosphorus content (with liquid fertilizers), isn't generally the case for the Potassium content, though.

    Most importantly, I was talking specifically for a tomato/pepper formula as requested by the thread starter. For that purpose I'd chose the product that actually has the lowest phosphorus content, in order to be able to raise the K proportion without having excess in P. To me that was/is just obvious. And I still see the cheapness with a few micro elements (regarding some products) as a disadvantage.

  • hydro_esox
    Original Author
    14 years ago

    Okay, im back with more questions

    I ended up buying a water soluable (NPK) 9-15-38, Calcium Nitrate, and Magnesium Sulfate.

    I just want to make sure my Calculations are correct or at least close enough i wont kill my plants. (tomatoes and peppers)

    solution is grams per 1 liter

    The NPK premix: .55 grams equals N~ 49-50 ppm
    P~ 82-83 ppm
    K~ 210 ppm

    CalNite: .65 grams equals Ca~123 ppm
    N~ 100 ppm

    MgS: .60 grams equals Mg~59 ppm
    S~ 78 ppm

    Toatals N 150 ppm
    P 82 ppm
    K 210 ppm
    Ca 123 ppm
    Mg 59 ppm
    S 78 ppm

    Is this sufficient? Did I do the math right?

    Thanks in advance

  • lucas_formulas
    14 years ago

    Unfortunately you did forget to transfer P(K2O) and K(P2O5) in actual P and K in order to get elemental PPM.

    Here are my results:

    Both "proposals" are as close as I can get to adequate formulas for maturing or advanced plants of that kind. The actual concentration of the nutrients with this amount of ELEMENTAL ppm should turn around 1.7-1.9 mS/cm and will obviously equal 750-950 ppm with a /500 conversion rate. But as I don't know the exact components used for the 9-15-38 product, I can only give an approximation here of what they'll actually read with that formula.

    REMINDER: Elemental ppm of such formula are never to be confused with ppm measured by any TDS or ppm meter (with any conversion rate). As these instruments can't measure any elemental ppm, but convert EC measurements to those of theoretical NaCl(/700) or PCl(/500).

    These formulas would be what I'd consider close to sufficient and balanced in most cases. As for tomatoes or cucumbers, the concentration could be increased to 2.2 or up to 2.5 mS/cm, depending on plant size, temperatures, yield and growing rate and last but not least if you want to push things a bit or not.

  • lucas_formulas
    14 years ago

    PS: sorry, there is a rather insignificant mistake with some maths somewhere, - but I will not promptly point it out for a change, but wondering if someone can find it instead ;-)

  • hydro_esox
    Original Author
    14 years ago

    Lucas I made a mistake on the mix NPK: what i actually baught was 10-16-38 (N= 1% ammoniacal 9%Nitrate nitrogen)
    The chemicals listed are: Potassium Phosphate, Potassium Nitrate, and Ammonium Phosphate.

    When you say elemental ppm ( i understand why we would need to isolate P and K) of P2O5 and K2O how are you getting the elemental %'s in those? Or if you can point me to a website with the information that would be greatly appreciated.

    Here is a link that might be useful: Gainer 10-16-38 Label Details

  • hydro_esox
    Original Author
    14 years ago

    I might have answered my own question

    P2O5 is 44% P
    K2O is 83% K

    Is this right or am i completely wrong here?

  • lucas_formulas
    14 years ago

    Fortunately, the P-K ratio stays about the same, because the (NPK) 9-15-38 was the only of many I would really recommend for it's good (well thought out) proportions. These actually are ideal to get a decent proportion between P and K! Well, actually X-16-38 isn't that much different, which is good for you.

    Here are the formulas to convert conventional NPK to elemental and vis versa.

    N=N

    P x 2.291=P2O5
    P2O5 x 0.437=P

    K x 1.205=K2O
    K2O x 0.83=K

    Next step: actual % x10 = actual ppm if 1gram is dissolved in 1 liter of pure water.

    Again the reminder: do not conclude any concentration in ppm (as in used by any "TDS-meter") from so called elemental ppm. There is no co-relation with standard conversion rates of any popular instruments!

  • wordwiz
    14 years ago

    Simple answer:

    Get some Tomato-tone fertilizer, put a tablespoon in a gallon of water and aerate for a day. Add enough of it to your water to get to the recommended ppm. If you want more nitro during the veg stage, add a teaspoon of Fish Emulsion to the mix, as not all the N in T-T is water soluble.

    YMMV,

    Mike