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Pool Professionals
Professional-grade products. Expert support. Built for your business.


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Eco-friendly, easy-to-use solutions to keep your pool clean and clear.


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Reliable solutions & delivery. Sustainable treatment for public systems.


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Pool Products
HASA has the chlorine, algaecides, and sanitizers you need to keep your pool or spa clean and clear.

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Hot Tub Products
Shop our full line of Hi-Temp spa care products, including Eco-Safe Clarifiers and pH Increasers.

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Ancillary Products
Our eco-friendly water treatments are science-backed and purposefully focused.

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Mini-Bulk Program
We deliver a premium 12.5% sodium hypochlorite solution for sanitizing commercial pools and large-scale water systems.

Blog
Learn from water chemistry experts.


Training and Support
Meet our educational resources and support options


Safety Data Sheets
Download SDS sheets for HASA products.


Pool Chemical Calculator
Achieve balanced chemistry easily.

Liquid Chlorine For Pools
A service professional’s guide that's been made simple.


Orenda Academy
For water chemistry & professional pool management knowledge.


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See where our products are sold near you with this tool. 

About HASA
Learn about HASA's commitment via the returnable packaging model.

Careers
Explore open positions with HASA.

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Terry Arko

Terry Arko brings more than 40 years of experience in the recreational water industry and currently serves as Technical Content and Product Training Consultant for HASA Pool, makers of HASA Sani-Clor. His career spans service and repair, retail sales, chemical manufacturing, technical service, commercial sales, and product development—giving him a uniquely comprehensive perspective on water chemistry from both the field and the lab. A respected educator and thought leader, Terry has written over 200 published articles on water chemistry and has been teaching chemistry-focused courses for more than 30 years. His ability to translate complex science into practical, real-world understanding has made him a trusted resource for pool professionals seeking safer, smarter, and more consistent water care. Terry is a Certified Pool Operator (CPO) Instructor with the Pool & Hot Tub Alliance (PHTA) and serves on the Recreational Water Air Quality Committee (RWAQC). In 2025 he was presented the Pool Nation Lifetime Achievement Award. Terry is driven by a lifelong commitment to education, innovation, and advancing industry standards through knowledge.

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