Plant Magic Hydro Feed Chart – Hydro A&B Doses and EC
Plant Magic's own published ESSENTIAL Hydro schedule. Week by week, in millilitres per litre of water.
- All dosesper litre
- Total EC0.8 – 2.2
- Base feedHydro A & B, 2–4ml of each
Every figure is millilitres per litre of water. A 50-litre reservoir at 3ml takes 150ml of Hydro A and 150ml of Hydro B. Flower 9 is a plain-water week, which is why the whole column is blank.
Getting it right
- The chart opens with a cutting week, and flowering starts again at 1. Cutting 1 is the week the plant goes into the system. When the lights change to twelve hours the count resets, so Flower 1 is the first week of flowering.
- Hydro A and Hydro B go in at the same rate as each other. Where the chart says 3ml, that is 3ml of A and 3ml of B for every litre in the tank.
- Add A to circulating water, then B — never the two together. Undiluted they react and the calcium falls out as a white sludge. Let the pump mix A right through before B goes anywhere near the tank.
- The whole crop drinks from one tank. There is no medium to soften a mistake, so measure with a jug rather than by eye and read the EC before the solution reaches the roots.
- The EC target moves every week. Plant Magic publish it as 0.8, 1.0 and 1.2 through Cutting 1, Grow 1 and Grow 2, then 1.4, 1.4, 1.6, 1.6, 1.8, 2.0, 2.2 and 1.8 across Flower 1 to 8, finishing at 0.6 for the plain-water week. That is total EC in the tank, tap water included.
- A standing reservoir gets stronger, not weaker. Plants take water faster than they take salt, so EC climbs as the level drops. Top up with plain water to hold the level and change the solution out rather than correcting it forever.
- Set pH last and check it again the next day. Every bottle you add moves it, and it keeps moving as the plants feed. Correct it after the feed is fully mixed, not before.
- Keep the tank cool and aerated. Warm water holds less oxygen and root problems start there. An air stone and a lid that keeps light off the solution do more for a hydro run than any additive.
- Magne-Cal+ is the one starred item. Plant Magic mark it "if usage required" — it goes in when the plants ask for more calcium and magnesium, which is common on reverse-osmosis or soft water and under strong LED light. It doubles from 0.5ml to 1ml at Flower 4.
- Evolution 2.0 is sprayed, not poured. It is a ready-mixed foliar tonic applied one or two times a week as needed, so its row reads "Spray" rather than a dose. Mist it with the lights off.
- The chart's Ignition Boost is Plant Magic Boost. It is the early-bloom stimulant, 2ml per litre from Flower 1 through to Flower 8.
- PK 13/14 starts at 1.5ml here. It holds at 1.5ml for Flower 4 and 5, then goes to 2ml through Flower 8, and stops for the final week.
- This is the ESSENTIAL schedule. Plant Magic also publish an ULTIMATE version with extra bottles. The doses above belong to the ESSENTIAL chart only.
Everything on the chart
Hydro A & B
From £11.49
2–4ml of each, all the way to the final week
Root Stimulant
From £58.95
2.5ml, Cutting 1 to Flower 2
Evolution 2.0
From £9.49
Foliar spray, once or twice a week
Magne-Cal+
From £8.49
0.5ml, then 1ml from Flower 4
Plant Magic Boost
From £28.49
2ml, Flower 1 to Flower 8
PK 13/14
From £10.49
1.5ml to 2ml, Flower 4 to Flower 8
Common questions
Why does the week count go back to 1 at bloom?
Because the two stages are counted separately. The chart opens with Cutting 1, then Grow 1 and Grow 2. The moment the lights go to twelve hours you start again at Flower 1, so the flowering doses stay lined up with the plant however long you vegetated for.
How do I mix A and B into a reservoir?
With the pump running, add all of the A, let it circulate, then add the B. Straight into each other the two concentrates react and the calcium drops out. Additives go in after that, and pH is set last.
My EC keeps climbing between changes — why?
Because the plants drink water faster than they take up nutrient, so what is left behind gets stronger. Top the tank up with plain water rather than more feed, and replace the whole solution when it drifts off the week's target.
Do I have to use Magne-Cal+?
Plant Magic star it as "if usage required". It earns its place when leaves show a calcium or magnesium shortage, which is most common on reverse-osmosis or soft water and under strong LED lighting.
What happens in Flower 9?
Nothing but water. The last column is blank because that week is plain water — no base feed and no additives.
Growing in coco or soil instead?
Plant Magic publish a separate ESSENTIAL schedule for each medium. See the Plant Magic coco feed chart, or the full feed charts index.
Shop the full Plant Magic range
Figures as published by Plant Magic on their ESSENTIAL Hydro Schedule, plantmagic.co.uk. Always read the label on the bottle you own. Plant Magic is a trade mark of its owner.