Shop
  • Deals
  • Deal checker
  • Black Friday
  • Buying guides
  • Brands
  • Stores
Travel
  • Flight deals
  • Hotel deals
Company
  • Research
  • Press
  • deal.ai apps
Black Friday 2026
  • Walmart
  • Best Buy
  • Target
  • TVs
  • Laptops
  • Headphones
  • Apple
  • Gaming
  • Vacuums
  • Kitchen
  • Toys
  • Smartwatches
  • Tablets
  • Furniture
  • Mattresses
© Deal.ai Inc.
TermsPrivacy
Deal.ai › Compare

General Hydroponics FloraPro Calcium + Micros vs Jack's Nutrients Magnesium Sulfate Epsom Salts

These are not substitutes. FloraPro Calcium + Micros is the calcium and micronutrient backbone of a two-part commercial feed, while Jack's Magnesium Sulfate is a straight magnesium and sulfur booster. Buy FloraPro if you run a calcium-nitrate-based program and need calcium plus chelated iron and trace elements in one A tank. Buy Jack's Epsom Salts if you already have a base feed and only need to correct magnesium and sulfur, especially in coco or under LED. Owners of both report clean dissolving and consistent lots; neither is a complete fertilizer on its own.

  • Choose the FloraPro Calcium + Micros if you want a single A-tank product that delivers calcium and chelated micronutrients for a full commercial crop cycle.
  • Choose the Jack's Magnesium Sulfate if your base nutrient already covers calcium and you only need a magnesium and sulfur boost.

Prices

  • General Hydroponics FloraPro Calcium + Micros: $25.95 at DS Garden Supplies (checked today)
  • Jack's Nutrients Magnesium Sulfate Epsom Salts: $76.77 at Walmart (checked today)
  • Difference: the General Hydroponics FloraPro Calcium + Micros is $50.82 cheaper than the Jack's Nutrients Magnesium Sulfate Epsom Salts today
General Hydroponics
General Hydroponics FloraPro Calcium + Micros 14-0-0 + 17% Ca

General Hydroponics FloraPro Calcium + Micros

General Hydroponics FloraPro Calcium + Micros 14-0-0 + 17% Ca

$25.95at DS Garden SuppliesChecked 1 h ago
See all prices and details
Visit DS Garden Supplies
Pros
  • Supplies calcium and six chelated micronutrients in one product
  • Nitrate-dominant nitrogen (13.1% of 14%) suits continuous feeding
  • No fillers or dyes; lot-tested for repeatability
  • Runs unchanged through veg and bloom alongside a B tank
Cons
  • Must stay separate from Grow, Bloom or Late Bloom in concentrate
  • No magnesium or sulfur; needs a partner product
  • Powder requires full dissolution before injector use
Jack's Nutrients
Jack's Nutrients Magnesium Sulfate Epsom Salts Water-Soluble Fertilizer, 25lbs

Jack's Nutrients Magnesium Sulfate Epsom Salts

Jack's Nutrients Magnesium Sulfate Epsom Salts Water-Soluble Fertilizer, 25lbs

$76.77at WalmartChecked 3 h ago
See all prices and details
Visit Walmart
Pros
  • Pure magnesium sulfate heptahydrate with low heavy-metal testing
  • Corrects magnesium and sulfur without adding nitrogen
  • Granules dissolve clear and store well in a 25 lb bag
  • Fits the Jack's 3-2-1 program directly
Cons
  • No calcium, nitrogen or micronutrients
  • Not a standalone feed
  • Oversupplementing magnesium can lock out calcium and potassium

What separates them

General Hydroponics FloraPro Calcium + MicrosJack's Nutrients Magnesium Sulfate Epsom Salts
Role in a feed programA-tank backbone supplying calcium and micronutrients all cycleStraight Mg and S booster added to an existing base feed
Guaranteed analysis14-0-0 with 17% calcium plus six chelated micronutrients100% magnesium sulfate heptahydrate, no nitrogen
Nutrients suppliedNitrogen, calcium, boron, copper, iron, manganese, molybdenum, zincMagnesium and sulfur only
Form and solubilityWater-soluble powder, no fillers or dyesWater-soluble granules, dissolves clear
ChelationIron and other traces chelated for stability in solutionNo chelates; simple salt
Mixing rateDissolved by weight per gallon for the A tank3.2 dry ounces per 100 gallons at 150 PPM N label rate
Best mediumAny hydroponic medium, commercial systemsCoco, low-magnesium soil, RO water, LED rooms
PackagingSingle SKU powder25 lb bag

Price history

$69.99$6.47
Nov 9Nov 10
  • General Hydroponics FloraPro Calcium + Micros: lowest $6.47 on Nov 9 at PADI-Dja; $30.52 on Nov 10.
  • Jack's Nutrients Magnesium Sulfate Epsom Salts: lowest $16.95 on Nov 9 at Evolve Garden Supply; $69.99 on Nov 10.

Prices at every store

General Hydroponics FloraPro Calcium + Micros

  • DS Garden SuppliesNew

    In stockReturn policy

    $25.95Checked 1 h ago
    Visit DS Garden Supplies
  • AmazonNew

    Availability unknown

    As an Amazon Associate, Deal.ai earns from qualifying purchases.

    $95.00Free shippingChecked 1 h ago
    Visit Amazon

Also available at

  • Healthy HydroCheck price at Healthy Hydro
  • BetterGrow HydroCheck price at BetterGrow Hydro
  • BLACK LABELCheck price at BLACK LABEL
All 2 stores and price history →

Jack's Nutrients Magnesium Sulfate Epsom Salts

  • WalmartNew

    In stockSold by Esbenshades Garden CenterReturns: Sold by a Walmart Marketplace seller; returns go to the seller under the seller's returns policy.

    $76.77Free shippingChecked 3 h ago
    Visit Walmart
  • Mass HydroponicsNew

    In stock

    $69.99+ $72.00 shippingChecked 3 h ago
    Visit Mass Hydroponics
  • AmazonNew

    Availability unknown

    As an Amazon Associate, Deal.ai earns from qualifying purchases.

    $76.77Free shippingChecked 3 h ago
    Visit Amazon

Also available at

  • eBayCheck price at eBay
  • Evolve Garden SupplyCheck price at Evolve Garden Supply
  • Jack' NutrientsCheck price at Jack' Nutrients

Store links may earn us a commission.

All 3 stores and price history →

Specs compared

SpecGeneral Hydroponics FloraPro Calcium + MicrosJack's Nutrients Magnesium Sulfate Epsom Salts
NPK ratio14-0-0—
Total nitrogen14.0%—
Ammoniacal nitrogen0.9%—
Nitrate nitrogen13.1%—
Calcium17.0%—
Chelated calcium0.47%—
Boron0.06%—
Copper0.02%—
Iron0.30%—
Manganese0.09%—
Molybdenum0.007%—
Zinc0.02%—
Show all 28 specsShow fewer specs
SpecGeneral Hydroponics FloraPro Calcium + MicrosJack's Nutrients Magnesium Sulfate Epsom Salts
Weight—25.0000
Nutrient Material Type—Granular
Nutrient Application—Hydroponic and Soil Nutrient
Magnesium Sulfate Content—Magnesium Sulfate, heptahydrate 100%
Mixing Rate—3.2 dry ounces in 100 gallons of water
Feed Strength—150 PPM N
Product Type—Concentrated
Type—General Purpose
Form—Dust

What reviewers say

Jack's Nutrients Magnesium Sulfate Epsom Salts

Growers who use it describe it as a straightforward, reliable source of magnesium that dissolves well and fixes yellowing leaves in coco and hydroponic setups. Complaints center on the bulk bag, dust and the need to measure carefully rather than on the product's performance.

What people mention
  • DissolvingPraisedGrowers say the granules dissolve readily in water with little leftover residue in reservoirs.
  • GreeningPraisedUsers report yellowing between leaf veins clearing up after adding it to their feed.
  • DustCriticisedSeveral owners note the granules are dusty when poured and scooping makes a mess.
  • PackagingMixedThe 25 lb bag is seen as good value for large gardens but awkward to store and reseal.

Questions and answers

Can I use these two together?
Yes. They cover different nutrients, so a base feed plus Jack's Epsom Salts plus a calcium and micronutrient source like FloraPro is a normal combination. Keep FloraPro separate from other concentrates and combine only in the diluted tank.
Which one do I need for a calcium deficiency?
FloraPro Calcium + Micros. It carries 17% calcium plus chelated traces. Jack's Epsom Salts supplies no calcium and will not fix the problem.
Which is better in coco coir?
Coco holds potassium and leaches magnesium, so most growers run both: a calcium and micronutrient source like FloraPro plus a magnesium sulfate boost like Jack's. Neither alone covers coco's demands.
Is the Jack's product a complete fertilizer?
No. It is 100% magnesium sulfate heptahydrate, so it only adds magnesium and sulfur. You still need nitrogen, phosphorus, potassium, calcium and micronutrients from other products.
Which lasts longer per unit of feed?
Jack's is dosed at 3.2 dry ounces per 100 gallons, so a 25 lb bag makes a very large volume of stock. FloraPro is dosed as a constant A-tank component, so its use tracks your reservoir turnover.
Do I need chelated iron if I use Epsom Salts?
Yes, from another source. Jack's Epsom Salts contains no iron. FloraPro supplies 0.30% chelated iron, which stays available across a wider pH range.

Ask our shopping agent

It checks today's price at every store, compares the alternatives and answers in about a minute.

Enter to send, Shift+Enter for a new line

More comparisons

  • General Hydroponics FloraPro Calcium + Micros 14-0-0 + 17% Ca vs Cropsalt 1lb Starter Pack
  • General Hydroponics FloraPro Calcium + Micros 14-0-0 + 17% Ca vs Cropsalt 5lb Set
  • Jack's Nutrients Magnesium Sulfate Epsom Salts Water-Soluble Fertilizer, 25lbs vs Cropsalt 1lb Starter Pack
  • Jack's Nutrients Magnesium Sulfate Epsom Salts Water-Soluble Fertilizer, 25lbs vs Cropsalt 5lb Set

Buying guides that pick them

  • Best soluble fertilizer salts for hydroponics
Rec. use
—
Garden
Rec location—Indoor, Outdoor
Size—25 lbs
Brand—Jack's Fertilizer
Plant category—Flowers, Fruits, Vegetables
Product net content uom—Pound
Product net content parent—25 Pound