Copper Sulfate Crystals
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- $ 21.99
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- $ 21.99
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Copper Sulfate Crystals (99% Pure)
Professional-grade 99% pure copper sulfate crystals for algae control, Bordeaux mixture, root clearing, and copper deficiency correction. Lab tested for purity — trusted by growers, pool pros, and homeowners since 1989.
Ideal Applications
FEATURES
🧪 99% Pharmaceutical-Grade Purity
Lab tested to confirm 99% copper sulfate pentahydrate — no fillers, binding agents, or impurities that reduce effectiveness or interfere with precise applications like Bordeaux mixture.
🌊 Broad-Spectrum Algae Control
Effective against green, blue-green, and filamentous algae in pools, ponds, irrigation canals, and water features. Works at trace concentrations — a little goes a long way.
🔬 Tested for Heavy Metals
Independently lab tested for heavy metal content to verify suitability for agricultural, horticultural, and livestock applications.
🌿 Bordeaux Mixture Ready
The foundation of the classic 4-4-50 Bordeaux mixture used in organic orchards and vineyards worldwide. High purity ensures correct reaction with hydrated lime for consistent results.
🌱 Plant-Available Copper Source
Corrects copper deficiency in sandy, peat, and high-pH soils. Copper supports enzyme systems, photosynthesis, and cell wall formation — applied to soil or as part of a foliar mix.
🔧 Root Intrusion Control
Kills roots inside sewer lines and drain fields without damaging pipe materials or disrupting beneficial soil bacteria outside the pipes. One treatment can last 6–12 months.
💧 Water-Soluble Crystal Form
Dissolves readily in water for accurate dilution across all applications — pool treatment, foliar sprays, or footbath solutions. No grinding or pre-mixing required.
📦 Indefinite Shelf Life
Stable crystalline form maintains potency indefinitely when stored in a cool, dry location. Buy in bulk with full confidence in long-term effectiveness.
🐄 Livestock & Hoof Care
Widely used in copper sulfate footbaths to help control hoof rot and digital dermatitis in cattle and sheep. Industry-standard treatment on commercial dairy and beef operations.
🎯 Multi-Use Value
One product serves pool treatment, pipe maintenance, garden disease control, soil correction, livestock care, and science education — exceptional value per pound.
SCIENCE BEHIND THE FORMULA
How Copper Works — and Why Purity Matters
Copper sulfate (CuSO₄·5H₂O) is one of the most well-studied inorganic compounds in agriculture and water treatment. Its effectiveness depends on releasing free copper ions (Cu²⁺) in solution — and the concentration of those ions depends directly on product purity. At 99% purity, Greenway Biotech copper sulfate delivers the expected Cu²⁺ concentration with no guesswork.
Copper as a Plant Micronutrient
🌿 Enzyme Activation
Copper is a required cofactor for enzymes including cytochrome oxidase and superoxide dismutase. Deficient plants show wilting tips, pale new growth, and reduced disease resistance.
🌾 Cell Wall Integrity
Copper contributes to lignin biosynthesis, which strengthens cell walls and improves structural integrity. Crops on sandy or high-organic soils are most frequently deficient.
🌸 Photosynthesis & Reproduction
Copper is required for plastocyanin, a protein involved in the electron transport chain during photosynthesis. Low copper can reduce yield and pollen viability in flowering crops.
How Copper Ions Kill Algae and Fungi
⚡ Cell Membrane Disruption
Cu²⁺ ions bind to sulfhydryl groups on proteins in algae and fungal cell membranes, disrupting membrane permeability and causing cell death. This mechanism works at very low concentrations — typically 0.1–0.5 ppm for algae.
🔬 Enzyme Inhibition
Copper ions inhibit key enzymes in photosynthetic organisms, blocking the electron transport chain. Algae are far more sensitive to this than higher plants, which is why trace doses control algae without harming aquatic vegetation at proper rates.
🌿 Bordeaux Mixture Chemistry
When copper sulfate reacts with hydrated lime (calcium hydroxide), it forms a colloidal copper hydroxide that adheres to plant surfaces. As the pH drops on the leaf surface (from rain or dew), Cu²⁺ is slowly released — providing long-lasting fungicidal protection against downy mildew, apple scab, and grape diseases.
Why 99% Purity Is Critical
🎯 Precise Dosing
Lower-purity products (often 85–96%) deliver unknown Cu²⁺ concentrations per measured dose. For fish ponds where the margin between effective and toxic is narrow, 99% purity is essential for safe, accurate treatment.
🌿 Bordeaux Mixture Reliability
Impurities in copper sulfate can interfere with the lime reaction, resulting in unstable mixtures with poor adhesion. 99% purity ensures consistent reaction chemistry every time.
APPLICATION RATES & DIRECTIONS
Water Treatment Applications
| Application | Amount | Frequency | Method |
|---|---|---|---|
| Swimming Pool (10,000 gal) | ½ teaspoon | Every 10–15 days | Add to skimmer basket |
| Small Pond (1,000 gal) | ¼ teaspoon | Monthly as needed | Dissolve and distribute |
| Fountain / Water Feature | Pinch per 100 gal | Bi-weekly | Add to circulation |
Plumbing & Drain Applications
| Application | Amount | Method | Notes |
|---|---|---|---|
| Toilet Root Control | 1–2 lbs | Flush at night | Let sit overnight |
| Septic Treatment | 2 lbs | Via toilet | Once per year maximum |
| Drain Field | 2–3 lbs | Distribution box | Professional recommended |
Garden & Agricultural Applications
| Application | Rate / Recipe | Use |
|---|---|---|
| Bordeaux Mixture (4-4-50) | 4 oz copper sulfate + 4 oz lime + 10 gal water | Fungal disease prevention |
| Soil Copper Correction | 1–2 lbs per 1,000 sq ft | Copper deficiency |
| Tree Soil Application | ¼ lb per tree | Apply to soil, not foliage |
Livestock Applications
| Application | Concentration | Notes |
|---|---|---|
| Cattle Footbath | 2–5% solution (2–5 lbs per 100 gal) | Hoof rot and digital dermatitis prevention |
| Sheep Footbath | 5% solution (5 lbs per 100 gal) | Foot rot treatment — consult a veterinarian |
HOW TO USE
Pool & Pond Algae Treatment
- Calculate water volume (length × width × average depth × 7.5 for rectangular pools).
- Measure ½ teaspoon per 10,000 gallons. For ponds without fish, scale proportionally.
- Pre-dissolve crystals in a bucket of warm water before adding to the water body.
- Add solution near the pump return or distribute evenly across the surface.
- Run the pump for 4–6 hours after treatment. Monitor and reapply every 10–15 days as needed.
Bordeaux Mixture (Fungicide Spray)
- Use only plastic or wood containers — copper reacts with metal.
- Dissolve 4 oz copper sulfate in 5 gallons of water in one container.
- In a second container, mix 4 oz hydrated lime in 5 gallons of water.
- Slowly pour the lime solution into the copper solution while stirring (never reverse this order).
- Test pH with litmus paper — mixture should read 7.5–8.0. Add small amounts of lime to raise pH if needed.
- Apply immediately — Bordeaux mixture does not store well. Spray on dormant or actively growing plants as appropriate for the target disease.
Root Control in Sewer Lines
- Flush 1–2 lbs of copper sulfate crystals down the toilet at night when water usage is minimal.
- Allow crystals to sit in the line overnight (6–8 hours minimum) for maximum contact time.
- Flush the toilet in the morning to clear the line. Repeat annually or as needed.
- For severe blockages or drain field issues, consult a plumber before treatment.
Soil Copper Deficiency Correction
- Confirm copper deficiency with a soil test before applying — copper accumulates and is difficult to remove once over-applied.
- Apply 1–2 lbs per 1,000 sq ft and work into the top 2–3 inches of soil.
- Water in thoroughly after application.
- Retest soil in 6–12 months before reapplying.
Pro Tip: Test Bordeaux Mixture pH Before You Spray
The #1 mistake with Bordeaux mixture is skipping the pH check. If the mixture is too acidic (below pH 7.0), free copper ions remain in solution and can cause leaf burn — especially on young growth. Dip a piece of litmus paper into the finished mixture before spraying. If it reads below 7.5, add a small amount of hydrated lime in water, stir, and retest. A properly buffered mixture at pH 7.5–8.0 adheres better, releases copper more slowly, and protects foliage without phytotoxicity.
When Copper Sulfate Is the Right Choice
- Recurring algae in pools, ponds, or irrigation water where you want a proven, low-dose treatment
- Organic orchards and gardens requiring Bordeaux mixture for fungal disease prevention
- Root intrusion in sewer lines where you need a slow-contact, non-caustic treatment
- Soils confirmed deficient in copper via soil test — particularly sandy, peat, or high-organic soils
- Livestock operations managing hoof health with copper sulfate footbaths
When to Consider Other Options
- Fish ponds with koi or trout — consider Chelated Copper EDTA or consult an aquatic specialist for safer dosing options
- Soils that are already copper-sufficient — over-application leads to copper toxicity, which suppresses earthworms and beneficial microbes
- Powdery mildew on sulfur-sensitive plants — Zinc Sulfate or sulfur-based alternatives may be less phytotoxic in hot conditions
COPPER SULFATE CALCULATOR
SAFETY & HANDLING
Personal Protective Equipment (PPE)
- Wear chemical-resistant gloves (nitrile or rubber) when handling crystals or solutions
- Wear safety glasses or goggles — copper sulfate solution is an eye irritant
- Use a dust mask when measuring or pouring dry crystals to avoid inhalation
- Wash hands thoroughly with soap and water after any handling
- Avoid contact with skin, eyes, and clothing
Storage Guidelines
- Store in the original sealed container in a cool, dry location (below 77°F preferred)
- Keep away from direct sunlight and moisture — copper sulfate is hygroscopic and will clump if exposed to humidity
- Store away from incompatible materials: alkaline substances, strong acids, aluminum, iron, and galvanized containers
- Keep out of reach of children and pets
- Do not store near food, animal feed, or drinking water supplies
Application Precautions
- Never use metal (aluminum, galvanized, or iron) containers or tools — copper reacts with these metals
- Do not apply to ponds, lakes, or water bodies containing fish without first calculating safe copper concentrations — fish toxicity varies with water hardness and species
- Do not apply near wells, cisterns, or drinking water intakes
- For septic systems, do not exceed 2 lbs per treatment and limit to once per year — excessive use can disrupt beneficial septic bacteria
- For soil applications, confirm copper deficiency with a soil test first — over-application accumulates and is difficult to remediate
- Do not apply foliar copper sulfate in temperatures above 85°F — phytotoxicity risk increases
First Aid
- Eye contact: Flush immediately with clean water for 15–20 minutes, lifting eyelids. Seek medical attention if irritation, redness, or pain persists
- Skin contact: Remove contaminated clothing. Wash affected area thoroughly with soap and water. Seek medical attention if irritation persists
- Ingestion: Do not induce vomiting. Rinse mouth with water. Contact Poison Control at 1-800-222-1222 or seek emergency medical attention immediately
- Inhalation: Move to fresh air immediately. If breathing is difficult or symptoms persist, seek medical attention
Refer to the Safety Data Sheet (SDS) for complete safety information including emergency response procedures.
COMPLETE YOUR SYSTEM
Pair copper sulfate with these products for complete garden, soil, and crop management programs:
Zinc Sulfate 35.5%
Corrects zinc deficiency alongside copper in soils with multiple micronutrient gaps. Commonly applied together in tree fruit and vegetable programs.
Urea 46-0-0
High-nitrogen fertilizer to support crop recovery after correcting copper deficiency. Promotes vigorous new growth following micronutrient treatment.
Dolomite Lime
Raises soil pH in acidic soils where copper toxicity risk increases. Also supplies calcium and magnesium for balanced fertility alongside micronutrient programs.
Sulfur Powder
Alternative or complementary fungicide for pH-sensitive plants and additional disease control in orchards and vineyards where Bordeaux mixture is used.
FREQUENTLY ASKED QUESTIONS
Is copper sulfate safe for swimming pools?
Yes, when used at the recommended rate of ½ teaspoon per 10,000 gallons, copper sulfate is safe for swimmers. It effectively controls algae at concentrations well below any health concern. The EPA has established drinking water standards for copper at 1.3 ppm — pool treatment concentrations are far below this threshold. Always pre-dissolve crystals before adding to the pool and run the pump after treatment.
How do I safely treat a fish pond with copper sulfate?
Fish ponds require extreme caution. Fish toxicity depends on water hardness — copper is more toxic in soft water (low calcium and magnesium). As a general rule, never exceed 0.25 ppm total copper in a fish pond, and use only ¼ of the standard dose as a starting point. Koi, trout, and tilapia are particularly sensitive. Always treat only a portion of the pond at one time, monitor fish closely for 24 hours after treatment, and have aeration running. When in doubt, consult an aquatic specialist before treating any pond with fish.
How do I make Bordeaux mixture and does it work for organic gardening?
Yes — Bordeaux mixture is approved for use in certified organic production under the USDA National Organic Program. To make the standard 4-4-50 formula: dissolve 4 oz copper sulfate in 5 gallons of water in a plastic container; in a separate container, mix 4 oz hydrated lime in 5 gallons of water; then slowly pour the lime solution into the copper solution while stirring. Test the pH — it should read 7.5–8.0 on litmus paper. Apply immediately as the mixture does not store. For a deeper guide, see our Complete Guide to Bordeaux Mixture.
How does copper sulfate work for sewer root control?
Copper ions are toxic to plant root cells at the concentrations reached inside a pipe. When you flush copper sulfate crystals at night, they dissolve slowly and move through the line, contacting root masses that have infiltrated through joints or cracks. The copper kills the fine feeder roots on contact without harming the main root system of the tree outside the pipe. Unlike caustic drain cleaners, copper sulfate won't damage pipe materials (clay, PVC, cast iron) or disrupt the septic system when used at recommended rates. One treatment typically lasts 6–12 months.
My soil test shows copper deficiency — how much should I apply?
For deficient soils, apply 1–2 lbs of copper sulfate per 1,000 square feet, worked into the top 2–3 inches of soil and watered in well. Sandy soils and high-organic soils (peat, muck) are most commonly deficient. Important: copper accumulates in soil and does not leach readily, so do not re-apply until a follow-up soil test confirms the deficiency persists. Over-application can suppress earthworms and beneficial soil microbes. Always base copper applications on a confirmed soil test result.
What are the most common uses for copper sulfate around the home and garden?
Copper sulfate has an unusually broad range of applications. For a comprehensive overview, see our article on 7 Reasons to Keep Copper Sulfate Handy in Your Home. Common uses include pool and pond algae control, Bordeaux fungicide for gardens and orchards, root intrusion control in drain lines, copper deficiency correction in garden soil, livestock hoof footbaths, and educational crystal-growing projects.
GROW WITH CONFIDENCE
Product Quality & Testing
- Independently tested by third-party laboratories for purity and heavy metal content
- 99% copper sulfate pentahydrate — verified by lab analysis
- CDFA registered product — compliant with California Department of Food and Agriculture requirements
- Professional-grade crystals suitable for agricultural, horticultural, and industrial applications
Hassle-Free Return Policy
If you're not completely satisfied, we offer a 90-day money-back guarantee. Return the unused portion in its original packaging and we'll process a full refund — no hassle, no questions asked.
Environmental Responsibility
- Transitioning to compostable and recyclable packaging materials
- Eco-friendly production and distribution methods
- Committed to education on safe, responsible, and minimal-use application practices
- Support for sustainable agriculture in California's San Joaquin Valley
Charitable Contributions
1% of all profits go to our foundation, focused on improving educational opportunities for children.
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