Botanicare 5gal Cal-Mag Plus 2-0-0 (48/PL)

Botanicare Cal-Mag Plus (2-0-0) is a highly fortified calcium, magnesium, and iron supplement designed to correct common deficiencies in hydroponic and soil-based growing systems. This 5-gallon format is well-suited for commercial cultivators and high-volume gardens that rely on reverse osmosis water or coco coir media, where calcium and magnesium depletion is an ongoing concern. Cal-Mag Plus can be used as a reservoir additive or applied directly as a foliar spray.

Cal-Mag Plus Specifications

The following table covers the key product specifications sourced from the canonical row attributes and product description.

Why Choose Cal-Mag Plus

Many nutrient programs, particularly those formulated for general-purpose use, do not supply enough calcium and magnesium to compensate for the variables growers encounter in real-world setups. Cal-Mag Plus addresses this gap directly. It is a concentrated, highly fortified supplement that delivers chelated calcium, magnesium, and iron in a single liquid solution that mixes easily into existing feed schedules.

Growers using reverse osmosis water face a particular challenge: RO filtration strips out naturally occurring minerals, including calcium and magnesium, which plants require in consistent supply throughout the vegetative and flowering stages. Without supplementation, deficiency symptoms — interveinal chlorosis, blossom end rot, tip burn, and slow overall development — tend to appear well before growers expect them. Adding Cal-Mag Plus to the reservoir restores those mineral levels to a range that supports normal plant function.

Coco coir presents a similar issue. Coco fiber has a natural affinity for calcium ions, binding them in the media and reducing their availability to plant roots. Growing in coco without a dedicated cal-mag supplement almost always results in calcium and magnesium deficiency over time, even when a complete nutrient formula is in use. Cal-Mag Plus is explicitly recommended by Botanicare for coco coir applications for this reason.

The foliar application option gives growers a fast-response tool when deficiency symptoms appear mid-cycle. A diluted foliar spray can deliver calcium, magnesium, and iron directly through leaf tissue, providing quicker uptake than waiting for root-zone correction to take effect. This makes Cal-Mag Plus a practical addition to any corrective toolkit, not just a reservoir supplement.

• Corrects calcium, magnesium, and iron deficiencies — addresses three of the most commonly encountered secondary nutrient shortfalls in hydroponic and soilless growing.
• Formulated for RO water use — restores the mineral profile that reverse osmosis filtration removes, giving plants a consistent baseline to work from.
• Recommended for coco coir media — compensates for the natural calcium draw inherent to coco fiber substrates.
• Dual application method — works as a reservoir additive or a foliar spray, giving growers flexibility in how and when they apply it.
• 5-gallon format — sized for high-volume gardens and commercial operations where smaller containers would require frequent reordering.

Best Uses for Cal-Mag Plus

Cal-Mag Plus fits into a wide range of growing setups and is particularly well-matched to scenarios where secondary nutrient availability is compromised by water quality or substrate chemistry.

• Reverse osmosis water systems — the most common application; add to RO feed water before mixing nutrients to rebuild a baseline mineral profile that supports root uptake.
• Coco coir-based grows — use throughout the growing cycle to offset the cation exchange behavior of coconut fiber, which binds calcium preferentially and can create persistent deficiency even in well-fertilized plants.
• Hydroponics (DWC, ebb and flow, NFT, drip) — suitable for any recirculating or run-to-waste hydroponic system where calcium and magnesium supplementation is needed as part of a complete nutrient program. Pairs well with other Nutrients & Additives such as Earth Juice Hi-Brix Molasses for soil-based feeding schedules.
• Foliar correction during deficiency onset — when interveinal chlorosis or calcium-related tip burn appears, a foliar spray of diluted Cal-Mag Plus can deliver nutrients directly to leaf tissue faster than root-zone feeding alone.
• Supplementing base nutrient programs — use alongside any brand’s grow, bloom, or micro formula to fill secondary nutrient gaps that single-part or two-part formulas may not fully address. If you are already running a root-building additive like Heavy 16 Roots, Cal-Mag Plus complements it by targeting secondary nutrient supply rather than microbial or root-zone chemistry.
• High-volume commercial production — the 5-gallon container size reduces per-application cost and limits the frequency of supply runs in large-scale operations.

Sources & Further Reading