Block Covers

SKU: 4INBC

HBX Block Covers are purpose-built for growers who want a cleaner, more controlled root zone. Designed to fit 4" and 6" rockwool blocks (as well as other compatible growing media), these black/white dual-layer covers help suppress algae growth, reduce evaporation, improve root-zone stability, and maintain a consistent environment around each plant.

Whether you're running a high-performance indoor cultivation facility or dialing in a small home grow, HBX Block Covers are one of the simplest and most effective tools to keep your substrate clean and efficient from veg to flower.

6 Mil Black/White Poly
1/2" Center Hole
1/4" Drip Stake Holes
Prevents Algae And Mildew Growth
Reflects Light Back Towards Plant
40 count

Size: 4"

Count: 40ct

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Description

6 Mil Black/White Poly
1/2" Center Hole
1/4" Drip Stake Holes
Prevents Algae And Mildew Growth
Reflects Light Back Towards Plant
40 count

Technical Specs

Overview

Material 6 mil black/white poly

Block Sizes 4" and 6"

Pack Size 40 count

Center Hole 1/2"

Drip Stake Holes 1/4"

Function Suppresses algae and mildew, reflects light back to the plant

Frequently Asked Questions

They're made for 4" and 6" rockwool blocks, and also fit other compatible growing media in those dimensions. Choose the size that matches your blocks.

They cap the exposed top of the block, which suppresses algae growth by blocking light, cuts evaporation from the media surface, and keeps the root zone more stable and consistent from veg through flower.

The dual-layer 6 mil construction blocks light from reaching the media (which is what starves algae) while the lighter face helps reflect light and heat rather than absorbing it at the root zone.

40 count per pack, in both 4" and 6".

General Questions

HBX products are stocked and fulfilled through Hydrobuilder.com and other authorized retailers. Use the Buy Now link on any product page, or see our Where to Buy page for details.

We don't sell or process orders through this site — it's a product catalog. Purchases go through our authorized retailers, who handle pricing, payment, shipping, and returns.

Yes. Contact us directly for wholesale pricing, volume tiers, and bulk order support and we'll work with you on your operation's needs.

Reach out through our contact page with your region and business details and we'll get back to you about becoming a distributor.

HBX is a commercial cultivation supply brand and part of the HydroBuilder Holdings family — the group behind three trusted cultivation brands with 80+ years of combined industry expertise. Every HBX product is built to the standard commercial operations demand, at a price that works for every grower.

Technical specifications are listed on each product page under the Technical Specs tab, with any available documentation under Resources. If you need something that isn't posted, contact us and we'll get it to you.

Minimums, if any, are set by the retailer fulfilling your order. For wholesale and bulk programs, contact us directly.

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Why Growers Choose HBX

Part of the HydroBuilder Holdings family — the same group behind 3 trusted cultivation brands and 80+ years of industry expertise. Every HBX product is built to the standard commercial operations demand, at a price that works for every grower.

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