Description
In stock now. The one-part flowering feed, designed specifically for British hard water.
IONIC Hard Water Bloom balances excess calcium before it locks out potassium and magnesium, with no heavy acid corrections pushing phosphate out of balance. It holds the tank near ideal levels for longer, meaning fewer water changes. The potassium to nitrogen ratio is set for flowering and yield.
Run vegetative growth on Hard Water Grow, then switch when flowering starts.
Key features
- One-part feed. No A and B mixing
- Designed for British hard water
- Balances excess calcium before it locks out K and Mg
- Fewer water changes, with the tank held near ideal for longer
- K to N ratio set for flowering and yield
- Dilution / Dose
- 6ml/L tapering to 5ml/L, joined by PK at 1ml/L from week 8 — EC runs higher than standard Hydro Bloom.
- When To Use
- Weeks 6–12; water-only flush in week 13 (hard/tap water)
- Substrate Fit
- Built specifically for hard water. IONIC doses differently by medium — Soil, Hydro, Hard Water and Coco each have their own schedule, so don't cross them over.
- Grower Notes
- Balances excess calcium before it locks out potassium and magnesium — built for British tap water. On soft or RO water, use Hydro Bloom instead. Add PK from week 8, and run Flower Boost weeks 5–9.
Good practice
- Add products one at a time, stirring between each. Never mix concentrates neat.
- Keep the tank covered — light in stored solution eventually means algae.
- On soft or RO water? Use the standard IONIC Hydro range and its own schedule instead.
- Use IONIC Tonic only where there is a recognised need: 0.5ml per litre for one week.
- Measure every dose — eyeballing is where most feed problems start.
The Ionic Range
IONIC is one system, twelve products — a dedicated Grow and Bloom feed for each growing medium, plus four boosters used across all of them. Here's the full range:
FAQs
What follows Hard Water Grow?
Hard Water Bloom, from week 6 — see Hard Water Grow.
Is this suitable for soft or RO water?
No, use Hydro Bloom instead — the EC targets and buffering here are built for hard water specifically.
Do I need PK Boost too?
Yes — add PK from week 8 through week 12.
How much of this will your grow actually need?
Tell us your medium, pot size and plant count. The Feed Chart Calculator builds your week‑by‑week chart with target EC, works out every bottle for the whole run, and puts them straight in your basket.