Feed Chart Calculator
We have fed every manufacturer's own feed chart into one calculator. Tell it what you are growing in, how many plants and how heavily you water, and it works out the whole run week by week — and what each brand's bottles will cost you from start to finish. It only ever baskets the bottles you actually need.
WORKS OUT WHAT ONE RUN NEEDS COMPARES THE COST BRAND BY BRAND
1 What are you growing in?
This sets how often the plants drink, and which feeds are suitable.
2 Pot or block size
Water use is worked out from this, so it drives the whole calculation.
Substrate volume, not the pot's stated capacity if you fill it short.
3 How many plants?
1 How does the feed reach your plants?
The one thing that changes how much you get through for the same plants.
2 How much does each plant drink?
Per plant, per day, at peak flower. It is what sets how much feed you get through.
1 Cycle & strength
1 Silicon
2 Pest prevention
1 Which feed?
The run is every bottle for your whole cycle. In the mix is the most products you ever add to one tank, at the busiest week.
Cheaper does not mean worse. Every feed on this list is a full schedule that will take a plant from week one to the chop. What the price gap mostly buys is bottles and fine control, which is what In the mix is showing you. The bigger lines are not a con either. More parts means more you can push on deliberately, if that is how you like to grow.
If this is an early run, the cheap end is a perfectly good place to be.
Same dose either way — this only picks which bottle you buy.
Your feed chart
Tank size only changes this chart — it makes no difference to what you buy.
Mix to the target EC — not the millilitres
Feed charts are written for 0.0 EC water. Whatever your tap water already reads counts towards the target, so the ml/L below is a starting point and the EC row is the number that matters. Treat it as a ceiling, not a suggestion — and check your water's EC before you add anything.
How to mix, and what to do if you miss
- Fill the tank and read the EC of the plain water. That is your starting point.
- Additives first — root stimulants, enzymes, silicon.
- Base nutrients next, A and B in equal parts, using the ml/L as a rough guide.
- Stir, read the EC, adjust: more nutrient to come up, plain water to come down.
- pH last, once the EC has settled.
Add plain, pH-corrected water until it drops to the target. Too strong pulls water back out of the roots — burnt tips, curling, lockout — even in soaking wet media. Next time start at 60–75% of the ml/L and creep up.
Add a little more base, equal parts A and B, until it reaches the line. Under-fed shows as pale leaves and slow growth. Usual on very soft or RO water, or through the peak weeks when the plant wants the top of the range.
Above about 0.5 EC from the tap you will not reach the peak weeks without overshooting. Blend in RO, or filter.
1 Add to the program
Anything marked on the chart is part of the manufacturer's own schedule.
This is what the manufacturer's chart calls for over a full cycle, a starting point rather than a prescription. Untick anything you already have and the total follows. Mix to the target EC rather than the millilitres, and check your own runoff: what your plants actually drink will move these quantities either way.
Sixteen brands, fifty-five feeds. Advanced Nutrients, Athena, BAC, BioBizz, CANNA, Crazy Hills, Dutch Pro, FloraFlex, House & Garden, Hydrotops, Monkey Nutrients, Plagron, Remo, SHOGUN, Terra Aquatica and Veg+Bloom. Only the lines that suit your medium are ever listed, and nothing is in the basket until you pick one.
Where the numbers come from. Every figure is a manufacturer's own, and where two of their documents disagree the page says which one it followed. Athena Blended is their metric chart; Athena Pro is dosed by target EC from their weight table, cross-checked against the Pro feed schedule — a flat EC 3.0 from veg to harvest, mixed at their recommended 226 g per litre of stock. CANNA Coco ramps: the 40 ml/10 L on the bottle is the peak rate, not every week. SHOGUN Coco and Terra come off their printed LED feedchart; Samurai Hydro has no printed sheet, so it comes from their own online calculator. VBX is the Hydroponic Research 2026 chart and FloraFlex the Full Tilt schedule, both transcribed cell for cell. Dutch Pro is their four printed sheets, hard and soft water being different charts rather than different bottles; House & Garden is the UK PRO 8 Week chart; BioBizz is the 2020 organic schedule. Where a manufacturer prints no EC — House & Garden and BioBizz — none is shown rather than one being invented.
Feed strength moves the base only. Enzymes, root stimulants and boosters stay at their own published rates whatever strength you pick — that is how SHOGUN's own calculator behaves, and it is the right way round: you do not double an enzyme because you decided to feed harder.
Watering. The one water figure that changes what you buy is litres per plant per day. It is worked out from your pot size and how heavily you water, ramped across the cycle (veg is about 55% of peak), and you can type over it if you already know your own number. Dripper counts, shot sizes and runoff targets are deliberately not asked for — none of them change the total.
How to read a feed chart
Every nutrient manufacturer publishes a feed chart. They are all laid out differently, most are printed in millilitres per litre or grams per gallon, and almost none of them tell you the one thing you actually need to know before you order: how much of each bottle a whole cycle will get through. This calculator reads the chart for you, fits it to the length of run you are actually growing, and totals the bottles.
Why target EC beats millilitres
A feed chart's millilitres are written for pure water. If your tap water already carries an EC of 0.4, and the chart is written for RO at 0.0, then mixing to the printed millilitres puts you above the chart's own target before you have finished stirring. That is the single commonest way a healthy plant gets burnt, and it is why this calculator shows the target EC on every week where the manufacturer publishes one, and says so in an accent panel directly above the chart rather than in the small print.
Mix to the EC. The millilitres are how you get close; the meter is how you know. Where a manufacturer prints no EC at all, and House & Garden and BioBizz do not, none is shown rather than one being invented.
What actually changes what a run costs
Not brand loyalty, mostly. The figures that move the total are pot size, plant count and how heavily you water, because those decide how many litres of feed you mix over the cycle. Change the pot size on the first screen and watch the totals move: it is usually a bigger swing than changing brand.
The one water figure that matters is litres per plant per day. Dripper counts, shot sizes and runoff percentages are deliberately not asked for. They change how you deliver the feed; they do not change how much of it you mix.
Why the same grow costs £84 on one brand and £756 on another
Because the programs are not the same shape. A one-part powder with a single additive is doing a different job from a nine-bottle program with a separate booster for each phase. Some of that spread is genuine formulation difference, some is packaging, and a fair amount is that you are paying to ship water around the country when you buy a liquid. The cheapest full program on coco at the time of writing is a powder, and it is cheap for that last reason rather than because it is a lesser feed.
Price is one column of four on the feed screen for exactly this reason. Sort by cheapest if you want, but the other three columns are there so that the decision is an informed one rather than a race to the bottom of a list.
What "in the mix" means
It is the largest number of separate products you ever add to one tank, in the busiest week of the program. A feed with three in the mix is three bottles on the shelf and three measurements every time you mix; one with seven is seven of each.
Fewer is not automatically better. A program that splits its calcium and magnesium into its own bottle gives you a lever a one-part does not. But it is a real difference between two feeds that a price alone will never show you, which is why it has a column.
RO water, tap water, and what "written for 0.0 EC" means
Several charts state that they are written for reverse osmosis water at a starting EC of 0.0. That is not a recommendation to buy an RO unit. It is a statement about the arithmetic: the chart assumes your water contributes nothing, so anything your tap water does contribute counts towards the target on top of the nutrient.
In practice, on UK tap water at 0.3 to 0.5, you need slightly less nutrient than the chart says to land on the chart's own EC. The calculator warns you where this applies. Some brands go further and print a separate soft-water chart, and where they do, picking soft water switches the whole schedule rather than just the bottle.
What the last two weeks of every chart are doing
Almost every program tapers, and most finish on plain water. That final stretch is not the manufacturer being generous with your money. Feeding a full-strength solution up to the day you cut leaves the plant carrying nutrient it has not used.
The calculator keeps the taper welded to the end of your run. If you grow a longer cycle than the printed chart, it inserts the extra weeks at the plateau in the middle, exactly where the manufacturer's own instructions say to repeat, so the finish stays where it belongs instead of the chart simply running out.
Is this tool free, and do I need an account?
It is free and there is no account. Nothing goes in your basket until you choose a feed, and even then you can change or remove any line before you order. The totals are live shop prices at the moment you use it, and the page calls them a guide price, because prices and stock move.
This calculator is not affiliated with, endorsed by or approved by any of the brands it lists. It reads their published feed charts. Every dose comes from a manufacturer's own document or the product's own listing, and the one figure that is ours rather than theirs, the foliar spray rate of 0.5 litres per square metre, says so on screen. It is a starting point built from the manufacturers' numbers, not a substitute for reading your own runoff and your own meter.
