- 64x Cultiwool 6" x 6" x 4" Growing Blocks with Optidrain Technology
Cultiwool 6" x 6" x 4" Growing Blocks w/ Optidrain (64 Blocks/Case)
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/mo.
- 64 blocks per case provide the substrate volume needed for heavy feeding crops
- Bottom drainage grooves reduce root contact with standing water
- 6 by 6 by 4 inch blocks with a 38mm to 40mm pre-cut plug hole
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VOLUME PRICING
Commercial & Bulk Purchasing
We support operations & licensed facilities with volume pricing, dedicated account managers, and custom equipment consultation.
Who This Is For
- You are moving to large format rockwool because your current blocks are drying out too fast between feeds.
- You are upgrading to Optidrain blocks because stagnant water at the base is causing root health issues.
What We Found
- The donut ring on top is more than a gimmick, it keeps dripper stakes from tilting or falling out.
- These bottom grooves are deep enough to maintain airflow even when sitting on a flat flood table.
What Users Say
- Growers who switched to these blocks say they stopped scrubbing algae off their media every week.
- Users who moved from flat-bottom blocks say the drainage grooves let them increase feeding frequency.
Cultiwool 6" x 6" x 4" Growing Blocks w/ Optidrain (64 Blocks/Case)
Struggling with inconsistent water distribution and poor drainage in your hydroponic setup? The Cultiwool 6" x 6" x 4" Growing Blocks w/ Optidrain are engineered to solve these challenges, providing a professional-grade substrate that ensures every plant receives the exact hydration it needs for explosive growth.
These premium stonewool blocks are designed for growers who demand reliability. By utilizing advanced homogeneous distribution technology, Cultiwool eliminates dry spots and waterlogging, creating a stable root zone environment. Whether you are scaling up from Cultiwool 4" x 4" x 4" Growing Blocks or looking for a high-performance alternative to loose media, these blocks deliver the consistency required for commercial success. For even larger plant systems, you might also consider the Cultiwool 6" x 6" x 6" Growing Blocks w/ Optidrain.
What's Included
Features
🍩
Donut Ring Tech
Industry-first water chamber design ensures perfect dripper placement and homogeneous water distribution.
💧
Optidrain System
Advanced drainage technology provides optimal root zone conditions and prevents dangerous waterlogging.
🌊
Drainage Grooves
Integrated bottom grooves improve water flow and reduce ground contact to minimize pathogen risks.
🛡️
Algae Prevention
Black and white foil wrapping blocks light to prevent algae growth while optimizing light reflection.
📏
Large Format
Generous 6" x 6" x 4" dimensions provide ample space for robust root development in larger plants.
Specifications
| Specification | Value |
|---|---|
| Material | Premium European Stonewool |
| Dimensions | 6" x 6" x 4" (150mm x 150mm x 98mm) |
| Plug Hole Size | 38mm / 40mm |
| Quantity per Case | 64 Blocks |
| Special Features | Optidrain, Donut Ring, Drainage Grooves, Black/White Foil |
| Selling Unit | Case Only |
FAQs
What is Optidrain technology?
Optidrain is Cultiwool's proprietary drainage system designed to ensure that excess water leaves the block efficiently, maintaining the perfect air-to-water ratio for healthy root development.
How does the Donut Ring help with irrigation?
The Donut Ring acts as a water chamber that guides your dripper placement and ensures water is distributed homogeneously throughout the entire block rather than channeling down one side.
Do these blocks prevent algae?
Yes, the blocks come wrapped in a high-quality black/white foil. The black interior blocks light to prevent algae growth on the substrate surface, while the white exterior reflects light back to your plants.
What size rooting plugs fit into these blocks?
These blocks feature a standard hole that accommodates 38mm to 40mm rooting plugs, making them compatible with most propagation starters.
Why are there grooves on the bottom of the block?
The cross grooves improve airflow and drainage between the block and the surface it sits on, reducing the risk of root pathogens and improving overall plant hygiene.
Happy To Help
Questions About This Product?
Our specialists are happy to help. Call us or send a message and we'll get back to you within one business day (most of the time within a few hours.)
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