Clearer Water. Easier Care. Made Simple.
We carry industry-leading brands like BioGuard®, SpaGuard®, Water’s Choice, and FreshRain®—giving you the right solution for every water care need.
Spa Filters
Cleaner Water Starts Here
Shop replacement spa filters designed to keep your water crystal clear and your system running efficiently. A fresh filter improves water quality, enhances circulation, and helps reduce strain on your equipment.
Explore Spa Water Care Solutions
Balance your water to prevent problems
Keeping the right balance of your spa water is necessary. Balancers control scale, adjust pH and total alkalinity, and correct mineral imbalances.
How important is pH really?
Having the correct pH level in your spa is crucial to comfort and helps protect your equipment from corrosion and scale. The ideal pH is 7.2–7.6.
PH Increaser
- Raises the pH
- Protects equipment from corrosion due to low pH
- Balances water for bather comfort
PH Decreaser
- Lowers the pH
- Protects spa and equipment due to improper pH
- Prevents cloudy water due to high pH
- Balances water for bather comfort
Total Alkalinity Increaser
- Eliminates “pH bounce” by balancing total alkalinity
- Helps prevent equipment and surface corrosion
- 1 tbsp. per 100 gallons raises total alkalinity 25 ppm
Calcium Hardness Increaser
- Prevents corrosion of equipment
- Prevents degradation of spa surfaces
- 1 tbsp. per 100 gallons increases calcium hardness about 25 ppm
Killing bacteria is key to spa maintenance
In a spa, sanitizers are added to control the growth of bacteria and algae. Warm water makes sanitization essential for clean, comfortable water.
Brominating Concentrate
- Fast-dissolving brominating granules
- Dual-acting sanitizer and oxidizer
- Easy to use with no pre-dissolving needed
- Apply directly to water while pump is running
Chlorinating Concentrate
- Fast-acting and quick-dissolving
- Easy to use with no pre-dissolving needed
- Acts as both sanitizer and oxidizer
- Apply directly to water while pump is running
Brominating Tablets
- Compressed 1-inch brominating tablets
- Dissolve slowly and protect continuously
- Ideal for heavy bather loads and commercial spas
- Use in a brominator or floating dispenser
Destroy organic contaminants
Shocking the water removes body oils, perspiration, cosmetics, odors, and other compounds while restoring water clarity and comfort.
Enhanced Shock
- Multi-purpose shock with four benefits in one
- Restores sparkle and removes odors
- Treat and soak in as soon as 15 minutes*
- Compatible with chlorinated or brominated spas
Spa Shock
- Non-chlorine oxidizer
- Easy-to-use, quick-dissolving treatment
- Treat and soak in as soon as 15 minutes*
- Can be used with chlorine or bromine
*15 minutes is only recommended as long as free chlorine or bromine does not exceed label recommendation.
Restore sparkle to your spa water
Cleaners and clarifiers improve the water’s appearance, extend filter performance, and help protect spa surfaces.
Water Freshener
- Eliminates odors instead of covering them
- Makes spa water smell fresh
- Works well with any sanitizer
Anti-Foam
- Quickly eliminates surface foam
- For use with all sanitizer types
- For use in all spas and hot tubs
Phosphate Remover
- Helps protect equipment from calcium phosphate scale
- Immediately reduces high phosphate levels
- Can be used as a weekly treatment
- Ideal for salt spa systems
Stain & Scale Control
- Prevents scale formation and cloudy water
- Removes some scale build-up on spa surfaces
- Helps remove fresh metal stains
Spa System Flush
- Removes unseen build-up in spa plumbing
- Works with all sanitizer systems
- Works with all spa sizes
Filter Cleaner
- Breaks down oils and dirt in filter fabric
- Helps keep water clear with better filtration
- Easy-to-use sprayer applicator
Spatec For Spas
- Supports pristine water quality and comfort
- Keeps spa water cleaner with less effort
- Maintains ultra-clear spa water
- Kills and prevents algae growth
- Reduces bromine and chlorine use
Beautec For Spas
- Acts as a multiscale and multi-stain preventative
- Helps prevent oil scum buildup
- Continuously purges and cleans plumbing lines
- Protects spa heater and filter unit from mineral scale
303 Aerospace Protectant
- Repels dust, dirt, and stains on vinyl covers
- Protects surfaces from UV fading
- Premium water-based, silicone-free formula
Water Testing
When you come to our store, bring in a pint-sized sample of your pool or spa water and we will give you the prescription to perfect water balance. Free water test with any purchase — or just $5 without.
Water Care FAQ's
Balancing your spa water means adjusting pH, total alkalinity, and calcium hardness so your water stays comfortable, clear, and easy to maintain.
pH affects comfort, clarity, and equipment life. Low pH can cause corrosion, while high pH can cause cloudy water and scale buildup. The ideal range is 7.2–7.6.
Total alkalinity helps stabilize your pH. If it is too low or too high, your pH can bounce up and down, making water harder to manage.
Sanitizers help control bacteria, viruses, and keep your spa water clean, safe, and comfortable. Warm water makes proper sanitizing especially important.
Yes. Water’s Choice Pure Enzymes for Spas helps break down organics naturally, reducing the need for traditional chemicals while helping maintain cleaner, clearer water.
Chlorine and bromine are in the same family. Chlorine works quickly and is easy to manage, while bromine dissolves more slowly and provides longer-lasting sanitation in hot water.
Sanitizer levels should be checked regularly and maintained after use. The right routine depends on how often the spa is used and your water care system.
Shocking removes organics released by our bodies in a hot tub while helping restore water clarity.
Spa Shock is a non-chlorine oxidizer designed to help remove organics and restore water clarity without raising chlorine levels. Enhanced Shock is chlorine-based, works more quickly, and provides stronger sanitizing power. Enhanced Shock should not be used in bromine systems.
Most spas should be shocked weekly or after heavy use to help remove buildup, improve clarity, and reduce odors.
Some shock products allow spa use in as little as 15 minutes, as long as chlorine or bromine levels are within the product label’s recommended range.
Cloudy water can be caused by improper balance, low sanitizer, dirty filters, heavy use, or buildup from organics.
Foam is usually caused by organics, residual soaps from swimsuits, hair conditioners, and other contaminants entering the spa water.
Stain and scale control products help prevent mineral buildup, cloudy water, fresh metal stains, and scale on spa surfaces and equipment.
Hidden buildup can collect inside spa plumbing over time. A system flush helps remove unseen buildup from the lines and improves water quality.
Clean your spa filter regularly to remove organics and debris from the filter fabric. Clean filters improve water circulation and water clarity. Spa filters should also be chemically cleaned every 3–4 months to help maintain performance and extend filter life.
Yes. Bring a water sample to Blackthorne Spas for computerized water testing and easy-to-follow recommendations tailored to your spa. Water testing is FREE with any in-store purchase, or available for $5 without a purchase.
