Product selection support
Discuss water conditions, process position and current products.
Source photograph; appearance, grade and supplied packaging follow the agreed product documents.
Reduction, dechlorination & oxygen scavenging
Sodium Thiosulfate
STS
A reducing raw material for the relevant dechlorination procedure, specified by hydration form and process requirements.
Confirmed availableBase chemicals
- Chemical identity
- The original catalogue specifies Na₂S₂O₃·5H₂O; distinguish the anhydrous salt from the pentahydrate.
- Product form
- Solid; hydration form specified for the order.
Add application & specification details
Application value
Uses and application conditions
Residual-chlorine reduction & dechlorination; Pool pH, alkalinity & stabilizer balance
Use these checks to compare equivalent supply specifications and narrow the candidate range for your actual process.
Specification & document coordination
Align specification basis, test methods and grade-specific documents.
Packaging & supply coordination
Review quantity, packaging and destination requirements.
Specifications & selection
Specifications and order requirements
Discuss your current grade or operating conditions. ENVO codes identify sales requirements; manufacturer grades, supply specifications, test methods and document versions are confirmed for the selected product.
ENVO-STS-5H99Catalogue pentahydrate grade
Na2S2O3·5H2O ≥99%.
Application conditions & technical scope
Specify hydration, active components and oxidant-measurement basis. Select using current-batch documents and system residual monitoring.
Appearance and supplied form
Confirm the form before comparing specifications.
Check the required form, then compare the composition, specifications and test conditions of the specific grade.
Product forms to compare
Pentahydrate prismatic crystals; anhydrous product listed separately
Colorless to white
Appearance information supports initial screening only. Color cannot establish chemical identity, concentration or quality grade. Confirm the actual batch using supply documents and samples.
Appearance and technical references
These public sources help check product categories, possible appearances and general application limits. They do not replace the TDS, SDS or batch COA for a specific ENVO grade.
- Nacalai Tesque · Sodium thiosulfate pentahydrate
Colorless prismatic crystals; pentahydrate form
- Thermo Fisher Scientific · Sodium thiosulfate pentahydrate
Crystals, distinct from the anhydrous form
- ENVO Chemical · Sodium Thiosulfate ENVO original catalogue
Associates the product page with a historical photograph; does not establish the current batch or the rights chain
Application issues and troubleshooting
Sodium Thiosulfate — troubleshooting checks
Review symptoms, possible causes and verification steps together to prepare a more focused product-selection discussion.
01Abnormal oxidant residual before membranes after sodium thiosulfate treatment
- Possible causes
- Oxidant measurement basis, active reducing component or site mixing/monitoring may be mismatched.
- Investigation and resolution
- Specify free/total oxidant and process location; assess chemical quality separately from actual residual monitoring.
- Checks required
- Oxidant type, monitoring method, membrane model, current product and batch documents.
- Application limits
- Do not substitute products using a generic ratio or treat dechlorination feedstock as a complete membrane-protection program.
02Sodium thiosulfate assay and dosage comparisons are inconsistent
- Possible causes
- Pentahydrate/anhydrous forms or active-content measurement bases differ; storage may also affect condition.
- Investigation and resolution
- Align salt form and current testing basis, then compare under actual system monitoring.
- Checks required
- Pentahydrate/anhydrous basis; assay; insoluble matter; impurities; reaction/monitoring conditions; production/arrival timing, packaging and storage information.
- Application limits
- Crystal appearance and color cannot replace assay tests; acceptance documents must match this delivery batch.
03Problems persist downstream after dechlorination
- Possible causes
- Reducing-agent residual, feedwater changes or downstream membrane/biological conditions may not have been fully considered.
- Investigation and resolution
- Track oxidant removal separately from downstream water quality and membrane/biological compatibility, clarifying process limits.
- Checks required
- Inlet/outlet water and residual records, downstream use, current monitoring and operating information.
- Application limits
- Do not independently mix with acids or incompatible oxidants; follow the corresponding SDS and system procedures.
Applications
See where this product fits.
Technical documentation
Get the information your purchasing decision needs.
Technical data sheet
Product properties, test basis and specification details.
Safety data sheet
Composition, handling, storage and transport information.
Certificate of analysis
Batch-specific analytical items and results.
Certification & use documents
Review the scope for the product and destination market.
Packaging & delivery
Reference packaging: 25kg or 1000kg/bag. Actual packaging, labels and filled net weight are subject to the order and delivery documents.
Technical references & scope
Industry references describe general uses. Product specifications, certifications and application results require the corresponding supplier documentation.
More questions, answered.
Abnormal oxidant residual before membranes after sodium thiosulfate treatment — what should I check?
Specify free/total oxidant and process location; assess chemical quality separately from actual residual monitoring.
What should I compare when buying Sodium Thiosulfate?
Share the application, current product, purchase quantity and delivery location to help confirm a suitable specification. Key checks include: Pentahydrate/anhydrous basis; Content; Insoluble matter; Impurities; Reaction & monitoring conditions. Compare the current grade document and the same test basis before choosing an alternative.
Which documents should accompany a Sodium Thiosulfate enquiry?
Request the current grade-specific TDS and product SDS, the COA for the actual supplied batch, and any intended-use documents required for the destination. Share the application, specification, quantity and delivery requirements. Document version, batch coverage and public-release scope are confirmed for the specific request.
ENVO CHEMICAL
Discuss your water treatment needs
Share your application, current product or purchasing requirements to discuss a suitable supply option.