User manual

First things to know (please read, it matters)

✅ What the app does: it calculates how many grams of each fertilizer you need per 1,000 liters of water (g/m³), split into tank A and tank B; it checks salinity (EC), the quality of your water analysis and solubility; it takes your soil analysis into account if you grow in soil; and it tells you with a traffic light whether the result is reliable.

⚠️ What the app does not do: it does not replace your laboratory or your agronomist. Its recipes are under professional validation — that is why you will always see the notice "Professional recipes NOT released". Use it as a calculation and diagnostic tool, and confirm with your advisor before applying at scale.

🔴 If the app says "Do not release", it is protecting you, not failing. It will always tell you why and what to do.

How to install it on your phone

The app lives at app.nutrisurco.com and can be "installed" to keep it handy and capture without signal:

• Android (Chrome): open the address, tap the ⋮ menu (top right) and choose "Add to Home screen".
• iPhone (Safari): open the address, tap the Share button (the box with an arrow) and choose "Add to Home Screen".

The Nutrisurco icon (the blue drop) will appear among your apps. Open it from there anytime, with or without signal.

The app is available in English and Spanish — switch with the language selector in the header, and your choice is saved. Everything is translated, including Field mode and the glossary.

The header is fixed: the logo and the language selector stay visible as you scroll down. On a phone it shows compact, so it doesn't take space away from long forms; on a tablet or computer, at full size.

Activate your license (or try DEMO mode)

• Without a code, the app runs in DEMO mode: you can make full calculations, but only with the sample waters the app ships with — so you get to know the app, even though the result does not apply to your ranch.
• With your code (format NSA-XXXXX-XXXXXX, sent when you buy): tap "I have a license code", paste it and activate. It is saved on your phone. On activation, the app tells you which license you have — for example "Basic license active" or "Pro license active" — and, if a mode is missing, it invites you to upgrade your package.
• Your purchase email includes the line "What you bought:" with the package you purchased (for example "Basic — Field mode (Drum)" or "Pro — full water analysis (Tank mode)"), and for the professional plan it adds "· Agronomist/Consultant plan". Read it when you receive it: if it does not match what you paid, write to us right away and we'll fix it.
• Your package defines which modes open: Basic = Field mode · Advanced = Field mode with meter reading · Pro = everything (Field + full water analysis). You can upgrade anytime with the same code — request it from Nutrisurco® and it activates on your next start with internet.
• The app verifies your license over the internet from time to time. Offline it keeps working for up to 14 days in a row; after that it needs to connect once to renew. The first time you do need internet once, to confirm your license on the device.
• If one day the app tells you your license is not active (because it expired, or because you already used all the devices your plan includes), you will see a notice with the reason and your code stays visible. Nothing is deleted: not your code, not your calculations, not your waters, soils or logbook. As soon as it is resolved, the app reactivates itself the next time you open it with internet.
• Devices: your plan defines how many devices you can activate the same code on (Grower 1, Agronomist 3).
• When your license is a few days from expiring, Nutrisurco® may send you a reminder email, so you don't run out of service.
• No code? Below the activation field you'll see the button "Buy a license — from $900 MXN per year" and the line "No code? Visit nutrisurco.com": tap them and the app takes you straight to the site (https://nutrisurco.com/en/nutrisurcoapp/), where you can see the packages and request yours.

Choose your mode: 🛢️ Field (Drum) or 🔬 Pro (Tank)

Above the form there are two buttons: "Field (Drum)" and "Pro (Tank)". Choose according to what you have:

• 🛢️ Field (Drum) mode — for the grower who mixes in a drum and irrigates by time with a pump, without a water analysis or an injector. It is the mode the app opens in and the one most people use. Its step by step is in section 5.
• 🔬 Pro (Tank) mode — for those who have a lab water analysis and prepare their tank with an injector. Its step by step is in section 6. If your package is Basic or Advanced, you'll see it with a lock 🔒 — it opens with the Pro package.

Your first calculation in Field mode (step by step)

Field mode is designed to irrigate by time with a pump and drum. You only need to gauge once with your own drum. Three steps:

1. Time how many seconds your drum takes to fill with your pump (for example, 240 seconds).
2. Tell the app how many hours you irrigate each time and how many irrigations you do per week.
3. The app gives you the grams to weigh in Drum A and Drum B for each irrigation, the kg you use per week and —if you enter your area— the kg per hectare.

For the first step you don't need another stopwatch: next to the seconds field there is a ⏱ button. Tap it when you insert the hose and again when the drum fills, and the time is captured for you.

How to gauge correctly

For the gauge to be valid, measure after the pump (at the system outlet), with the whole flow entering the drum. The hose diameter or the adapters don't matter, as long as they carry the full flow to the drum. What does invalidate the gauge: diverting part of the flow while you measure, or measuring before the pump. If you change pump or well, gauge again.

How do you grow?

At the top of Field mode you choose soil or bag/pot (substrate). In substrate the app doesn't ask for a soil analysis and doesn't discount what the soil already holds, because in a bag or pot the plant feeds only on what you put in the irrigation.

How to apply the recipe

Always apply it in this order: full Drum A → rinse (a while with water only, to clean the line and avoid clogging emitters) → full Drum B → finish your irrigation. Never mix A and B in the same drum: calcium precipitates (it turns to stone).

Inside Drum B, the app numbers the steps with your real salts, with a golden rule: one salt at a time, and fully dissolve each one before adding the next. The order is first the sulfates, then the nitrates and mono-potassium phosphate (MKP) last.

The drum is your concentrate: the grams the app gives you are for the drum, not for all the water you irrigate, and they are per irrigation. Suction empties the drum in minutes, it does not "sip" it over the irrigation hours. That is why it is best to start with water only, inject the drum in the middle third of the irrigation, and close with water only.

If something won't dissolve

When a drum is too loaded, the app doesn't just warn in red: it gives you the concrete way out.

• ⛔ Won't dissolve → use a bigger drum, split it into 2 batches, or switch to another source of that nutrient.
• ⚠️ High load → stir well; if you see sediment at the bottom, add water or split the load in two.

Where your water comes from

Tell the app whether you irrigate with canal, river or well water. It doesn't change the calculation, but if it's from a well (or you don't know it) it will warn you: well water often carries salts and hardness, and without measuring EC you can salinize your crop without realizing. That's what the Advanced package and a conductivity meter are for. If you don't enter your water analysis, the calculation assumes clean water and tells you so on screen.

Report, history and DEMO

With a license, Field mode also generates a printable report (your drums, your gauge, the protocol with rinse and a signature line) and saves your calculations in the history. Without a license (DEMO) it shows a fixed example so you can see how it works, and you can time your own drum and see your real flow; calculating with your pump, your hours and your irrigation requires the Basic package.

Your first calculation in Pro mode (step by step)

Pro mode is for those who have a lab water analysis. If your package is Basic or Advanced, you'll see it with a lock 🔒 — it opens with the Pro package.

Step 1 — Project name (required)

Write something that identifies the calculation, for example "San José Ranch — tunnel 2 — May". Without a name, the app doesn't calculate (that way each result is identified and traceable).

Step 2 — Crop and stage

Choose your crop (strawberry, raspberry, blueberry or blackberry) and its phenological stage (establishment, vegetative, flowering, fruiting…). Each stage has its own target recipe.

Step 3 — System

• Substrate: pots, bags, coconut fiber, etc.
• Soil: direct planting in the ground. Here you can also enter your soil analysis (Step 5).

Step 4 — Your water analysis (strongly recommended)

Check "Enter my water analysis", choose the unit your lab reports in —meq/L, ppm (mg/L) of the ion, or ppm of the element— and copy the values exactly as they come; the app converts for you. Also enter the measured EC (dS/m) and the pH. If you don't know which "ppm" your lab uses, ask them: the difference matters, because the same element changes a lot depending on the form it is reported in.

Each cell can carry its own unit. Next to each of the 11 water rows there is a small selector with that cell's unit. The rule in one sentence: copy the number as it comes on your report and tell the app which unit that cell is in. The top selector rules by default, so if you don't touch anything everything works the same. The CaCO₃ option appears only in calcium, magnesium, bicarbonate and carbonate, which is how labs report hardness and alkalinity.

The phosphorus cell accepts its four forms —H₂PO₄⁻, elemental P, PO₄³⁻ and P₂O₅—: choose the one your report shows and the app does the conversion.

⚠️ This avoids a common mistake: confusing elemental P with phosphate completely changes the amount of phosphorus that enters the calculation. That conversion used to be done by hand; now you pick it from a list.

💾 With a license you can save your analysis with a name ("North well") and fill it in with one tap next time, without re-typing.

As long as you haven't entered any value of your own water, a "Sample water" selector appears above, with two real, anonymised lab analyses: Sample 2 — alkaline well with iron, the one the app opens with, and Sample 1 — hard sodic well, kept there on purpose as a difficult case. The moment you type the first ion the selector disappears: from then on the calculation runs on your water.

Step 5 — Your soil analysis (soil system only, optional)

Enter your soil's fertility (N, P, K, Ca, Mg, S, pH and organic matter). If your lab reports K/Ca/Mg in meq/100 g, choose that unit and the app converts. The app classifies each nutrient against the Mexican standard NOM-021 (SEMARNAT) and reduces the target by up to a maximum of 20% for what your soil already holds high.

Next to the potassium, calcium and magnesium cells there is a selector, "K/Ca/Mg extraction method", with three options: I don't know, ammonium acetate pH 7 (exchangeable), or water/saturation extract (soluble). The same number means different things depending on how the lab measured it; that's why, if you don't declare the method —or if you declare "soluble"— the app stops classifying your K, Ca and Mg and explains it on screen. Your N, P and S are always classified.

⚠️ Prefer not classifying over classifying wrong: reading a "soluble" calcium with the "exchangeable" table could lead you to lime a soil that doesn't need it, and that blocks phosphorus, zinc and iron. If the method isn't on your report, ask your lab for "exchangeable bases by ammonium acetate pH 7".

Below the macronutrients there are five cells for Fe, Zn, Cu, Mn and B (in mg/kg). Enter them if they come on your report: the app shows them in the "Analysis interpretation" block, but doesn't grade them and they don't change your recipe. The good-or-bad range depends entirely on the extractant the lab used, so you read the number and your agronomist judges it.

The "Soil EC (dS/m)" field lets the app warn you if your soil already carries salt before you irrigate: whatever you inject adds to what is already there.

Below the result you'll see your soil contribution table, with a "Level (NOM-021)" column that combines the level and the discount in a single cell (for example, "Medium · −10%"). The scale is:

The app never subtracts your soil's ppm against the solution's mg/L: they measure different things. If your soil is high in a nutrient, it lowers the target by a percentage; the rest is still supplied by fertigation. The soil analysis is available in both modes when you plant in soil.

Step 6 — Acid and tank

• Acid for alkalinity: if your water has a lot of bicarbonate, the app calculates how much acid to use. The selector offers sulfuric 98% (the factory default), phosphoric, nitric and none. Its contribution enters the calculation (sulfuric as sulfur).
• Final tank (m³): optional. If you enter how many cubic meters of already-diluted final solution your system prepares, the app gives you the exact grams per tank.

Step 7 — Tap "Calculate nutrient solution"

How to read your result

The traffic light

The traffic light sums up at a glance whether the result is reliable:

The stars ★★★☆☆

They measure the quality of your data (not the app's): with your own water and your measured EC you'll get more stars than with the sample water.

The list of causes

Each ⛔ or ⚠️ tells you what's happening, how much and what to do. On salinity the app always puts the two numbers side by side —the EC your solution would have and the maximum for your crop and stage—: "Control EC 1.818 dS/m exceeds the maximum 1.322 (37% over). Nutrition IS achievable; salinity is not. → Review/blend your water or validate the target with your advisor." And if no fertilizer adjustment reaches the targets either, the notice says so in full: "And nutrition is not met either… With this water and these sources there is no acceptable recipe."

When the block is about salinity and your water is high in sodium or chloride, the app names them with their figure and tells you what is not obvious: no fertilizer removes them —they are not among the 11 elements the recipe adjusts— and they go into the EC in full. Turning sources off does not correct them; what does lower the EC is blending with cleaner water or treating the water.

The recipe: Tank A and Tank B

Fertilizers are split into two tanks because together they precipitate:

• Tank A: calcium nitrate and iron chelate.
• Tank B: sulfates and phosphates (potassium nitrate, MKP, magnesium sulfate, etc.).

Amounts come in g/m³ (grams per 1,000 L of final solution) and, if you entered your tank, in g/tank. Below you'll also see the liters of stock solution A and B according to your concentration factor — the same grams, in less water. Never mix the concentrated contents of A and B directly; they are injected separately into the irrigation.

The visual balance (Pro mode)

Above the recipe two charts appear: a salinity meter (EC), which turns green if your solution is on target and red if you go over the salt ceiling; and a "Did each nutrient reach its target?" chart, where each bar should reach the 100% line. The light green part is what your water already brings; the strong green, what the fertilizers add; and anything in amber is an excess from the water that can't be lowered.

The acid section

It gives you the mL/m³ of acid to neutralize the bicarbonate. It is a theoretical dose: confirm it with a small test and measure pH and EC before applying. Safety: always add the acid to the water, never water to the acid. Use gloves and goggles. That line also tells you which nutrient the acid contributes and reminds you that this contribution is already counted in your recipe.

🔬 Analysis interpretation (Pro only)

Below the result there is a collapsed block (closed, so it doesn't get in the way) with the calculations an engineer does routinely: your water's hardness and alkalinity as CaCO₃, the Ca:Mg:K ratios of your solution, and your soil micros if you entered them. The ratios and micros come without a traffic light, on purpose: we give you the numbers, not a verdict, because there are no published ranges by crop and stage. There, the judgment is yours or your advisor's.

Traceability

By tapping "Where did each number come from?" you see, element by element, how much your water adds, how much the acid and how much each fertilizer. Nothing is a black box.

The tools

Signable PDF report

Below the result, tap "Generate report": a printable version opens with your logo, the traffic light, the full recipe, the traceability and a signature line for your advisor to endorse it. Use "Save as PDF" from the print dialog. It works offline.

Report with your advisor's brand (Agronomist plan)

With the Agronomist plan, the form shows "My advisor details": enter your name (and, if you want, your license number, phone and logo). From then on your report reads "Prepared by: [your name] · for: [the client]" with your logo, next to the Nutrisurco one. On the base package this option doesn't appear.

Share your recipe (Field and Pro)

The "Share recipe" button builds a message with your drums or tanks, the calculated grams and the application protocol, and sends it via WhatsApp or your phone's share menu. The message opens with your calculation's name and carries at the end the notice that it is a guide.

History

The app saves your last 50 calculations on your own phone (they are kept with their recipe and their seal). Each mode has its own history, with date and time, and you can name each calculation. When you open one, the app shows you what was saved — with or without signal; if you want the result from today’s engine, tap Calculate again (that does need internet).

Irrigation scaling

Below the recipe you enter your m³ per irrigation and irrigations per week, and the app translates the recipe into grams per irrigation, kilos per week and how many days a 25 kg bag lasts. This doesn't change the recipe: it only converts it to your working units.

Saved waters and soils

Save your water and soil analyses with a name ("North well", the plot or the ranch) and load them again with one tap. Very useful if you serve several ranches.

EC logbook (Advanced or Pro package)

Each time you prepare the solution, you note the target EC (pre-filled) against the EC you measure with your meter. The list shows the difference with color: green if you're on track, amber if you drift more than 15%.

Two-water blender (Advanced or Pro package)

If your water is very saline and blocks the recipe, blend it with a cleaner one. Enter the EC of each and the EC you want to reach, and the app tells you the proportion and the breakdown in liters. It is a field estimate: confirm it with your meter.

Backup and restore via WhatsApp

Your data (history, waters, soils, logbook, advisor details) lives on your phone. You can save it to a file and send it to yourself via WhatsApp; if you change phone or clear the browser, you restore it. Your license code does not go in the backup: on the new device you activate it with your code, as always.

Glossary

EC? meq/L? chelate? exchangeable bases? At the end of the app there is a collapsible glossary with all the abbreviations and concepts explained in plain language.

Frequently asked questions

Which package do I have and how do I upgrade?

Your package (Basic = Field, Advanced = Field with EC, Pro = everything) comes with your code, and the app tells you on activation. If a mode appears with a lock 🔒, it's not in your package: request the upgrade from Nutrisurco® — you keep your same code and your data, and it activates on your next start with internet.

Beyond the package, the Agronomist plan is designed for the advisor who serves several growers: it adds up to 3 devices, folders by client or ranch in the history, and your professional brand (your name, license number and logo) on the reports you deliver. If you're interested, write to us.

Are g/m³ a dose per day or per irrigation?

Neither — they are a concentration: grams per 1,000 L of the final solution. Your real consumption = concentration × m³ you irrigate. That's what the irrigation scaling tool is for. (In Field mode it's different: there the grams per drum are per irrigation.)

I irrigate every 3–5 days, do I change the recipe?

No. The recipe is the solution's concentration; irrigating less often means consuming less solution, not making it stronger. Never make up for days without irrigation by raising the concentration: you'd spike salinity (EC) and damage roots.

What is the "Final tank" and how do I make my stock solution?

The final tank is the volume of already-diluted solution that reaches the emitter (the one that sets the EC). If you use an injector with a stock solution, the stock volume = final tank ÷ your concentration factor, and in each stock you dissolve the same grams the app gave you for that tank. Your injector dilutes it back when irrigating.

In Field mode, is the drum what I irrigate?

No. The drum is your concentrate, and its grams are per irrigation. Suction empties it in minutes — it doesn't last the irrigation hours. That's why it's best to start with water only, inject the drum in the middle third of the irrigation, and close with water only.

Which water does the DEMO calculate with, and why does "Do not release" sometimes come up?

In Pro mode, as long as you haven't entered your analysis, the app calculates with a sample water and lets you choose which one. It opens with Sample 2 — alkaline well with iron: that one comes out with a recipe and with iron warnings (at its pH the iron in the water is not credited, and emitters need watching). Sample 1 — hard sodic well is kept on purpose as a difficult case: it always blocks on salinity, with sodium and chloride as the culprits. In both cases the verdict is the correct one; for yours, enter your real analysis.

Can I apply the recipe directly to my crop?

The app gives you the best technical calculation available, but the recipes are in the process of professional validation. Use it with your advisor's support, start on a small section and monitor.

What is EC and why does it block so much?

Electrical conductivity measures the total salt of the water plus the fertilizers. Going over EC damages roots and crop, especially blueberry. That's why it's a limit the app won't let you cross silently: it compares the EC your solution would have against the maximum for your crop and stage, and if it goes over it tells you with both numbers in sight. And if what pushes it up is the sodium or the chloride in your water, it warns you, because no fertilizer removes them: there the way out is blending with cleaner water or treating the water, not switching salts.

Does it work offline?

Partly. Capturing works without signal: the app saves what you entered and calculates it on its own once coverage is back. Consulting what you already have saved also works offline, with its recipe and its seal. What does need internet is calculating a new recipe. Your licence, separately, stays valid for up to 14 days in a row without connecting.

The app looks odd or shows old text, what do I do?

The installed app keeps a copy of itself so it opens without signal (calculating still needs internet). After an update, close it completely and reopen it (sometimes twice); in a browser, force reload (Cmd/Ctrl+Shift+R). If your phone has the browser's automatic translation on, turn it off for this app.

Is my data uploaded anywhere?

Partly, and it is worth knowing exactly what. To calculate a new recipe, the data from that entry —project name, water analysis, soil analysis and the laboratory fields— is sent to the servers of the Controller or its providers, where it is kept for a maximum of twenty-four (24) hours. What is not uploaded: your history, your waters, your soils, the logbook and your advisor details, which live on your phone. The verification of your license code also travels. You can read the details in the Privacy notice.

Can I change the fertilizers?

Yes: under "Show advanced options" you can disable sources you can't get, and each group has a link to select or clear the whole group. The app recalculates and warns you if the target can't be met with the rest. ⚠️ Don't turn everything on for convenience: some commercial products don't yet carry their solubility data, and with those the app can't verify whether your drum dissolves. Only mark what you buy.

What's new by version

The app improves often. Here is a general summary of what has changed, from most recent to oldest. The way you use it doesn't change between versions: almost everything is improvements in clarity, transparency and precision.

Versions 1.67 to 1.84

The salinity block now always compares the two numbers —your solution's EC and the maximum for your crop and stage— and no longer stays silent when nutrients are missing as well; and if what pushes the EC up is the sodium or the chloride in your water, the app names them and tells you no fertilizer removes them. Pro mode ships with a second sample water (a real alkaline well) and opens with it; the sodic one is still available as a difficult case. The factory iron chelate moved to EDDHA 6 %, which holds up at high pH, and the app warns you if the chelate you picked does not suit your water's pH. In "My available fertilizers" the micronutrients are no longer jumbled together: the iron ones now have their own group. Locks name the package that unlocks each thing —in DEMO too—, a missing required cell is flagged and the app scrolls you to it, and Field mode became easier to use with a screen reader.

Versions 1.63 to 1.66

The app is clearer about what each plan includes and what you'd unlock by upgrading. The notice that the calculation is a guide now also accompanies the Field-mode report and the recipe you share. The link to the privacy notice, the button to request your license and more contact details in the purchase email were added.

Versions 1.43 to 1.62

A tidier interface, more even between the two modes, with new tools for the grower: the two-water blender and the backup of your data via WhatsApp. Activation became more reliable and a thank-you page guides you after paying.

Versions 1.33 to 1.41

The app understands your lab analysis better as it is delivered to you, and Field mode caught up with Pro. Handling of well water and saline soils improved, and the EC logbook, the by-client folders of the Agronomist plan and saving your analyses with a name were added.

Versions 1.22 to 1.32

One-tap activation from the email, a drum stopwatch inside the app, history ordered by mode and with names, and the result that can finally be seen at a glance. Sharing your recipe via WhatsApp and the report with the advisor's brand were added.

Legal notice

Nutrisurco.App is a calculation and diagnostic tool. It does not replace laboratory analysis, titration or professional agronomic judgment. Professional recipes remain NOT released until formal chemical and agronomic validation is completed. Application decisions and their technical supervision rest with the person who signs the report.

See also the Privacy notice and the Terms of use.