BioGreen Hydro Feed Chart – A&B Doses, EC and pH
BioGreen's own published Hydro A&B schedule. Week by week, in millilitres per one litre of water in the tank.
- All dosesper 1 litre
- pH5.4 – 6.2
- Base feedA&B, 1ml to 3ml
Every figure is millilitres per one litre of water. Multiply by the number of litres your reservoir actually holds — 3ml in a 50-litre tank is 150ml. A dash means the bottle is not used that week.
Getting it right
- Work out your reservoir volume before you measure anything. These are per-litre figures, so the number on the chart is almost never the number that goes in the tank. Fill the reservoir to its working level, note the litres, then multiply every dose by that.
- The A&B row is one figure for a two-part feed. Part A and Part B are separate bottles. Add one to the filled tank, let the pump circulate it, then add the other. Never pour A into B, and never into a half-filled tank.
- PK 13/14 and X-Blast are not run together. BioGreen print that instruction on the chart: PK 13/14 at Flower 3 and Flower 4, X-Blast from Flower 5 onwards. The grid shows both against the later columns, so pick one.
- X-Force is measured in fractions of a millilitre. 0.1ml per litre from Cutting 1 to Grow 4, 0.15ml from Flower 1 to Flower 9. In a 50-litre tank that is 5ml and 7.5ml — small enough that a syringe is worth having.
- Calgel carries no weekly dose on this chart. BioGreen give one instruction instead: if your tap water reads below EC 0.6, add Calgel until the reservoir reaches 0.6. Reverse-osmosis water always needs it.
- Check pH and EC daily in a recirculating system. Both drift as the plants drink and the tank level drops. pH belongs between 5.4 and 6.2.
- Top up with plain water, not fresh feed. The EC in a shrinking tank rises on its own. Bring the level back with water first, then read the EC and correct.
- Feed to the EC target for the week. BioGreen publish one for every column: 0.6–0.8 at rooting; 1.0–1.2, 1.2–1.4 and 1.4–1.6 through veg; then 1.6–1.8, 1.8–2.0, 2.0–2.2, 2.0–2.2, 2.1–2.3, 2.1–2.3 and 2.0–2.2 through flowering; 1.6–1.8 at Flower 8 and Flower 9; and 0.0–0.8 in the final plain-water week.
- The last column still has two bottles in it. Base feed, PK 13/14, X-Blast, X-Force and Garlic stop. Biozym goes in at 3ml and X-Bloom at 2ml.
Everything on the chart
BioGreen A&B
From £13.49
1ml to 3ml, Grow 1 to Flower 9
X-Rooting
From £31.95
2ml Cutting 1 to Grow 2, 0.5ml from Flower 3
Biozym
From £26.00
1ml rising to 3ml, through the final week
X-Bloom
From £44.95
1ml then 2ml, Flower 1 through the final week
PK 13/14
From £10.49
1ml to 1.5ml, Flower 3 to Flower 9
X-Blast
From £33.95
1.5ml then 1ml, Flower 5 to Flower 9
X-Force
From £36.99
0.1ml then 0.15ml, Cutting 1 to Flower 9
Garlic
From £24.49
1ml, Cutting 1 to Flower 9
Common questions
My reservoir holds 40 litres. How much base feed at Flower 2?
The chart says 3ml per litre, so 40 litres needs 120ml. Do the same multiplication for every other bottle in that row: X-Rooting 40ml, Biozym 40ml, X-Bloom 40ml, X-Force 6ml, Garlic 40ml.
Is this the same as the BioGreen coco chart?
Almost, but not quite. The base feed runs at 3ml at Flower 7 on this hydro chart and at 2.5ml on the coco one. Everything else matches. The BioGreen coco feed chart has the full coco figures.
Do I use PK 13/14 or X-Blast?
One or the other, never both. BioGreen print it on the chart: PK 13/14 at Flower 3 and Flower 4, then X-Blast from Flower 5 onwards.
I run reverse-osmosis water. What do I add first?
Calgel. It has no weekly dose on this chart. BioGreen say to bring the reservoir up to EC 0.6 with it before the base feed goes in.
Why does the base feed drop at Flower 8 and Flower 9?
The chart steps it down from 3ml to 2ml for Flower 8 and Flower 9, and the published EC target drops with it from 2.0–2.2 to 1.6–1.8. The last column after that has no base feed at all.
Figures as published by BioGreen on their own hydro feeding chart, biogreenuk.com. Always read the label on the bottle you own. BioGreen is a trade mark of its owner.