Hydrochloric Acid 32%

Hydrochloric acid for pools, also known as muriatic acid, is widely used in pools to lower pH levels, enhance water clarity, and boost chlorine effectiveness. Always refer to guidelines for safe dilution and handling. You can also use this for pool cleaning, acid wash.

Applications:

• Swimming Pool pH Adjustment
• Brick Cleaning & Concrete Etching
• Industrial Processes & Metal Preparation
• Mineral Processing

Guidelines for Brick Cleaning and Etching

1. Scrape off excess concrete or mortar and soak bricks with water.
2. Prepare a solution by mixing 1 part acid with up to 10 parts water.
3. Apply with a brush, wait for the reaction to stop (frothing), then rinse with water.

Hydrochloric Acid for Pools pH Adjustment Instructions

1. Add 100 ml of acid per 40,000 litres of pool water to lower pH by 0.1 (e.g., 7.9 to 7.8).
2. Run the pool pump for at least 1 hour after adding acid; retest and adjust pH as needed after 8 hours.

*Included in the cost is a $5 deposit for the 20L drum, which is reimbursable upon the return of the empty container.

Technical Reference

Technical Specifications

Applications & Use Cases

• Swimming pool pH reduction: Lowering pool water pH to the recommended range of 7.2–7.6 to optimise chlorine efficacy and bather comfort
• Pool acid washing: Deep cleaning of pool surfaces (plaster, pebblecrete, fibreglass) to remove calcium scale, algae staining, and mineral deposits
• Brick and masonry cleaning: Removal of mortar smears, efflorescence, and calcium carbonate deposits from clay bricks, pavers, and concrete surfaces
• Concrete etching: Surface preparation of concrete slabs prior to application of coatings, sealers, or epoxy floor systems
• Metal preparation and pickling: Removal of mill scale, rust, and oxides from mild steel and iron surfaces prior to galvanising, coating, or welding
• Industrial descaling: Removal of carbonate and silicate scale from heat exchangers, boilers, cooling towers, and process pipework
• Mineral processing: Ore leaching and pH adjustment in hydrometallurgical processes
• Water treatment: pH correction in industrial process water and wastewater neutralisation
• Food processing equipment cleaning: Descaling of stainless steel equipment where food-grade acid is specified (note: food-grade acid required; this technical-grade product is not certified for direct food contact)
• Tile and grout cleaning: Removal of grout haze and calcium-based staining from ceramic and porcelain tiles

Dosing Rates & Guidelines

All dosing rates are indicative based on standard Australian industry practice. Actual rates must be verified by site-specific water testing or surface assessment. Always test and adjust incrementally.

Dilution Instructions

Critical safety principle: Always add acid to water. Never add water to acid. Adding water to concentrated hydrochloric acid causes violent exothermic spattering and the generation of concentrated HCl fumes, which may result in severe chemical burns and respiratory injury.

1. Select appropriate PPE before commencing: Don chemical-resistant gloves (neoprene or PVC, minimum 0.4 mm thickness), chemical splash goggles (not safety glasses), a PVC or rubber apron, and respiratory protection appropriate for the concentration being handled (see Safety & Handling section below).
2. Prepare your dilution vessel: Use only chemically compatible containers — high-density polyethylene (HDPE), polypropylene (PP), or PVC. Never use aluminium, zinc, galvanised, or mild steel containers. Ensure the vessel is clean and dry. For large volumes, use a vessel at least twice the final solution volume to allow for safe mixing.
3. Measure the required volume of water first: Add the full volume of cold, clean water to the dilution vessel before any acid. For pool pH adjustment, this step is typically omitted — the acid is added directly to the pool water.
4. Measure the required volume of acid: Use a graduated HDPE or PP measuring jug dedicated to acid use only. Do not use metal funnels or containers.
5. Add acid slowly to water: Carefully pour the measured acid into the water in a slow, controlled stream. Do not splash. Stir gently with a chemically resistant rod (HDPE or glass) during addition. The solution will warm slightly — this is normal.
6. Allow to cool before use: Allow the diluted solution to return to ambient temperature before applying, particularly for masonry or surface applications.
7. Label the container immediately: Mark the container with the chemical name, concentration, date of preparation, and hazard pictograms in accordance with the Globally Harmonised System (GHS) / Australian Work Health and Safety Regulations.
8. For pool pH adjustment (direct addition): With the pool circulation pump running, slowly pour the measured dose of acid directly into the water in front of a return jet inlet. Do not pour near the skimmer box, pool steps, or in shallow areas where bathers may be present. Never pre-mix pool acid in a bucket of pool water — always add acid to the large body of water. Keep bathers out of the pool for a minimum of 30 minutes after dosing and retest pH before re-entry.

Common dilution ratios for 32% HCl stock:

Chemical Compatibility

Compatible materials for storage and handling:

• High-density polyethylene (HDPE)
• Polypropylene (PP)
• PVC (polyvinyl chloride) at ambient temperatures
• PVDF (polyvinylidene fluoride) for pump and valve components
• PTFE (Teflon) for seals and gaskets
• Viton (FKM) elastomers
• Borosilicate glass (laboratory applications)
• Fibre-reinforced plastic (FRP) with vinyl ester resin

Incompatible materials — do not use with hydrochloric acid:

• Metals: Aluminium, zinc, iron, mild steel, galvanised steel, copper, brass — react vigorously with HCl to produce hydrogen gas (flammable) and may cause container or equipment failure
• Stainless steel (304 grade): Susceptible to pitting and chloride-induced stress corrosion cracking; 316L grade offers limited resistance only at low concentrations
• Natural rubber: Degrades rapidly in concentrated HCl; use neoprene or EPDM alternatives
• Polycarbonate and acrylic (Perspex): Chemically attacked by concentrated HCl

Chemically incompatible substances — do not mix with hydrochloric acid:

• Hypochlorites (pool chlorine, sodium hypochlorite, calcium hypochlorite): Reacts to release chlorine gas (Cl₂), a toxic gas with an immediately dangerous to life and health (IDLH) concentration of 10 ppm. This reaction is severely hazardous and has caused fatalities in pool plant rooms. Under no circumstances should acid and chlorine products be mixed or stored in close proximity without adequate segregation.
• Sodium hydroxide / caustic soda/soda ash: Violently exothermic neutralisation reaction; causes spattering if unmixed.