Dutch Pro - Original Grow - Hydro/Coco A&B HW

Dutch Pro Original Grow Hydro/Coco A&B HW — Two-Part Base Nutrient for Hard Water Areas

Best for: Growers in hard water areas wanting a proven two-part hydroponic nutrient that won't overcomplicate the veg stage

Dutch Pro Original Grow Hydro/Coco A&B HW is a two-part mineral base nutrient designed specifically for hydroponic systems and coco growing during the vegetative stage. This is the hard water version — formulated to work with UK tap water rather than against it. It contains a balanced blend of macro and micronutrients (nitrogen, phosphorus, potassium, plus boron, manganese, and zinc) that plants absorb cleanly, leaving no residue behind. No padding, no marketing nonsense — just a working formula that's been proven over three decades of professional use.

How it compares

Dutch Pro sits in the mid-range professional category — serious quality without the premium markup.

• More affordable than Advanced Nutrients or House & Garden, comparable to General Hydroponics
• Simpler than 3-part systems (like Flora Series) — just two bottles to manage
• Hard water optimisation is relatively rare; most competitors sell a one-size-fits-all formula
• Proven track record in both hydro and coco, unlike single-medium specialists

You're paying for what's in the bottle, not fancy packaging or convenience features.

Usage guidance

Mixing
Fill your reservoir with water, add Part A at 2.5–3.5ml per litre, mix thoroughly, then add Part B at the same rate. Never mix A and B neat — always add to water first. Stir well.

For hydroponic systems
Works with NFT, flood and drain, drip irrigation, and deep-water culture. Aim for an EC of 1.8–2.0 for optimal uptake. Renew your reservoir solution every 7 days to keep nutrient availability stable.

For coco grows
Use the same dosage. Coco has minimal buffering, so this gives you full control over feeding strength. Water to roughly 10–20% runoff each feed.

pH management
Aim for 5.8 (range 5.6–6.2). Because nutrient addition raises pH, start at the lower end of the range. Dutch Pro recommend their pH Down (nitric acid-based, rather than phosphoric) for the veg stage if you need it.

Water type
This is the hard water formula, so it's built to handle typical UK tap water. Most UK tap water won't drastically affect results, but this version accounts for the extra calcium and magnesium already in hard water, so you're not doubling up unnecessarily.

Technical specifications

• Format: Two-part liquid base nutrient (Part A & Part B)
• NPK ratio: 4-2-6
• Micronutrients: Boron, Manganese, Zinc, plus other trace elements
• Recommended dosage: 2.5–3.5ml of each part per litre of water
• Target EC: 1.8–2.0 mS/cm
• Target pH: 5.8 (range 5.6–6.2)
• Formulation: Hard water optimised
• Available sizes: 1L, 5L, 10L, 20L
• Suitable for: All hydroponic systems, coco coir, hard water areas
• Usage stage: Vegetative growth (veg base nutrient)

Who this is for

• Growers in hard water areas (particularly UK) who want a nutrient formulated for their water type
• Hydroponic system users (NFT, drip, flood and drain, DWC) wanting a proven two-part base
• Coco growers looking for stable, clean feeding without overcomplication
• Both beginners and experienced growers — the simplicity works at any level
• Anyone wanting professional-quality nutrients without paying premium brand prices
• Growers who prefer straightforward two-part systems over multi-part complexity

Our take

This is proper working kit. Dutch Pro's been making nutrients for 30 years, and they haven't done it by cutting corners or chasing hype. For a veg base in hydro or coco, especially if you're on hard water, this delivers stable feeding and clean uptake without the fuss or the premium price tag.

If you want reliable two-part hydroponic nutrients that actually account for your water type, worth picking up while stock lasts. Mixes easily, doses predictably, and does exactly what it should, day in, day out.