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Aptus Massboost Cal-Mag & Sulfur Bud Development Supplement

Aptus Massboost Cal-Mag & Sulfur Bud Development Supplement

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SKU: AP16010

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Aptus MassBoost

Aptus MassBoost is a targeted flowering booster designed to prevent calcium and magnesium deficiencies while enhancing fruit set, flower density, and structural strength. Applied during key bloom weeks, it supplies essential Ca and Mg when plants need them most, supporting strong cell walls, efficient photosynthesis, and healthy development in soil, coco, and hydroponic growing systems.

  • Features & Benefits
  • Product Specifications
  • What is included?
  • Warranty Policy

Targeted Calcium & Magnesium Flowering Booster

MassBoost delivers precisely timed calcium and magnesium supplementation during critical flowering stages, helping plants maintain structural integrity, optimize photosynthesis, and maximize flower development without disrupting your base nutrient program.

  • Prevents calcium and magnesium deficiencies
  • Enhances fruit set and flower development
  • Strengthens cell walls, stems, and flowers
  • Supports chlorophyll production and photosynthesis
  • Designed for use in weeks 3, 5, and 7 of flowering
  • Compatible with soil, coco, and hydro systems

Stronger Flowers When It Matters Most

Aptus MassBoost ensures your plants receive critical calcium and magnesium exactly when demand is highest. By reinforcing plant structure and boosting photosynthetic efficiency, it helps growers achieve denser, heavier flowers and consistent performance during intensive flowering stages.

Why Aptus?

Aptus is trusted by professional growers worldwide for its science-driven formulations, premium raw materials, and uncompromising quality. Each product is designed to deliver maximum efficiency with minimal input, helping growers achieve consistent, high-quality results through precision nutrition.

Why Buy From Us?

At GreenThumbDepot, you're not just another sale to a faceless corporation. You're partnering with a team genuinely invested in your success. Our legendary customer service, combined with a promise of unbeatable prices, sets us apart. We're here for you, always.

Excellent 4.8 out of 5 based on 1,247 reviews
If I could rate 6 stars I would!
If I could rate 6 stars I would! My representative Edouard B. has been shockingly responsive! Like - oh my god - an actual SERVICE oriented company. He's dug into my odd connectivity issues I've been having - and following up in an AMAZINGLY timey manner. No shit. You'll be impressed! (And the price was also unbeatable, quick shipping...it's all PERFECT). Thank you Ed!!
Customer service was outstanding great…
Customer service was outstanding great people to deal with they understand your needs and they will do their best to fulfill them there is no way I can complain about them because they are the best help out there.Thanks green thumb depot. I'll definitely order from them again
The machine is doing just what my…
The machine is doing just what my salesman told it would do (I appreciate you Ed thank you) . The machine is what we need for our new business we're starting up, soon to be llc and licensed. We are getting a lot of clients wanting our services. Ed I will be needing more of your products, thank you again.
Fantastic
Great prices, fantastic customer service, and mind blowing shipping! Incredible. Will be using again and telling anyone in need.

FAQ Section

What is Aptus MassBoost used for?
MassBoost is used to prevent calcium and magnesium deficiencies while enhancing fruit set and flower development during flowering.
When should I apply MassBoost?
Apply during flowering weeks 3, 5, and 7. It can also be used in the vegetative phase if calcium or magnesium deficiencies appear.
What is the recommended dosage?
Use 5–10 ml per 5 gallons during flowering, and 2.5–5 ml per 5 gallons during vegetative growth if needed.
Which growing mediums can MassBoost be used in?
MassBoost is suitable for soil, coco coir, and hydroponic systems.
Does MassBoost replace a Cal-Mag supplement?
It provides targeted calcium and magnesium support but is intended as a booster, not a complete base nutrient replacement.
What sizes is Aptus MassBoost available in?
Aptus MassBoost is available in 1L, 5L, and 20L sizes.
Is MassBoost safe to use with other Aptus products?
Yes, MassBoost is designed to integrate seamlessly with the full Aptus nutrient line.

Specifications

Aptus MassBoost
SKU AP16010
Available Sizes 1L, 5L, 20L
NPK (Nitrogen) 5
Application Phase Flowering (Weeks 3, 5, 7), Vegetative (if needed)
Growing Media Soil, Coco, Hydroponics
Shipping Weight (1L) 3.3 lbs

What is included?

It includes:

  • Aptus MassBoost (Selected Size: 1L, 5L, or 20L)
  • Original Manufacturer-Sealed Container
  • Usage and Application Instructions

Warranty Policy

Please check out the manufcaturers website for Warranty related issues.

Aptus Massboost Cal-Mag & Sulfur Bud Development Supplement

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Aptus MassBoost

Aptus MassBoost is a targeted flowering booster formulated to prevent calcium and magnesium deficiencies while supporting strong fruit set and dense flower development. Applied at key stages of bloom, it reinforces cell structure and photosynthesis during high-demand growth periods. MassBoost helps plants maintain vigor, stability, and consistency throughout flowering. Available in 1L, 5L, and 20L sizes.

Product Overview

Specifications

What's Included?

Warranty & Returns


Product Overview

Aptus MassBoost is a specialized Ca/Mg booster designed to support flowering plants during peak metabolic demand. Applied during strategic bloom weeks, it strengthens plant structure, enhances photosynthesis, and supports uniform fruit development. Its concentrated formula helps prevent common calcium and magnesium deficiencies in intensive growing systems.

Key Features:
1. Calcium & Magnesium Support
2. Targeted Flowering Use
3. Strengthens Cell Structure
4. Enhances Photosynthesis
5. Concentrated Formula

wetanddry
wetanddry

Features and Benefits of Aptus MassBoost

Aptus MassBoost delivers essential calcium and magnesium during critical flowering stages when plants experience their highest nutrient demand. By reinforcing cell walls and supporting chlorophyll production, MassBoost helps promote strong floral development, improved structural integrity, and consistent performance in both hydroponic and soil-based systems.

Targeted Feeding

Ca Mg Support

High Concentration

Flower Development

Available in Different Sizes

How to Use

1. Flowering: Use during weeks 3, 5, and 7 at 5–10 mL per 5 gallons of water.

2. Vegetative (if needed): Apply 2.5–5 mL per 5 gallons to correct Ca/Mg deficiencies.

3. Mix thoroughly into nutrient solution before application.

4. Suitable for soil, coco, and hydroponic systems.

5. Monitor EC/PPM levels to avoid overfeeding.

6. Shake well before use.

7. Do not return unused solution to the bottle.

8. Store sealed in a cool, dark location.

Why Aptus?

Aptus is trusted by professional growers worldwide for its science-driven formulations, premium raw materials, and uncompromising quality. Each product is designed to deliver maximum efficiency with minimal input, helping growers achieve consistent, high-quality results through precision nutrition.

wetanddry
wetanddry
wetanddry

Why Choose Us

At GreenThumbDepot, you're not just another sale to a faceless corporation. You're partnering with a team genuinely invested in your success. Our legendary customer service, combined with a promise of unbeatable prices, sets us apart. We're here for you, always.

wetanddry

Customer Reviews


Trusted by authentic customer reviews from verified buyers worldwide.
If I could rate 6 stars I would!
If I could rate 6 stars I would! My representative Edouard B. has been shockingly responsive! Like - oh my god - an actual SERVICE oriented company. He's dug into my odd connectivity issues I've been having - and following up in an AMAZINGLY timey manner. No shit. You'll be impressed! (And the price was also unbeatable, quick shipping...it's all PERFECT). Thank you Ed!!
Customer service was outstanding great…
Customer service was outstanding great people to deal with they understand your needs and they will do their best to fulfill them there is no way I can complain about them because they are the best help out there.Thanks green thumb depot. I’ll definitely order from them again
The machine is doing just what my…
The machine is doing just what my salesman told it would do (I appreciate you Ed thank you) . The machine is what we need for our new business we’re starting up, soon to be llc and licensed. We are getting a lot of clients wanting our services. Ed I will be needing more of your products, thank you again.
Fantastic
Great prices, fantastic customer service, and mind blowing shipping! Incredible. Will be using again and telling anyone in need.


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FAQ Section

What is Aptus MassBoost used for?
MassBoost is used to prevent calcium and magnesium deficiencies while enhancing fruit set and flower development during flowering.
When should I apply MassBoost?
Apply during flowering weeks 3, 5, and 7. It can also be used in the vegetative phase if calcium or magnesium deficiencies appear.
What is the recommended dosage?
Use 5–10 ml per 5 gallons during flowering, and 2.5–5 ml per 5 gallons during vegetative growth if needed.
Which growing mediums can MassBoost be used in?
MassBoost is suitable for soil, coco coir, and hydroponic systems.
Does MassBoost replace a Cal-Mag supplement?
It provides targeted calcium and magnesium support but is intended as a booster, not a complete base nutrient replacement.
What sizes is Aptus MassBoost available in?
Aptus MassBoost is available in 1L, 5L, and 20L sizes.

Specs & Dimensions

Weight According to selected size
Brand Aptus
Available Sizes 1 L, 5 L, 20 L
Brand Aptus
SKU AP16010
N-P-K 5 - 0 - 0
Application Phase Flowering (Weeks 3, 5, 7)
Form Liquid
UPC 670541797150

Items in the box

Aptus Massboost Bottle

Manufacturer-Sealed Container

Warranty & Returns

Please check out the manufacturers website for Warranty related issues.

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