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Our spa calcium hardness increaser is vital to ensuring proper water hardness levels in your hot tub. Avoid corrosion, etching, and staining - aquadoc's professional Grade Hot Tub Calcium increaser is your best defense against soft water in your hot tub or spa.
Easy to use, add proper amount of increaser while equipment is on. The hardness increaser hot tub owners love - when it comes to Spa Chemicals calcium hardness increaser is a must have. 3 after determining hardness level goal, wait 20 minutes, then retest water. 4 run filter for 1 - 2 hours, made in the usa - 1 check your calcium levels, 2 1 ounce of AquaDoc's Calcium increaser will boost water's hardness level by 10ppm. Without hot tub chemicals calcium hardness can become unbalanced.




Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride. 5, 12. 5 lbs/200ppm. See package for instructions.


5, 000 gallons: 105 lbs to increase hardness 50ppm, 50 Lbs/200ppm. Dosage: 2, 25 lbs/200ppm. Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride.

20, 000 gallons: 1. 5 lbs to increase hardness 50ppm, 000 Gallons: 6. 25 lbs to increase hardness 50ppm, 50 Lbs/200ppm. 5, 000 gallons: 105 lbs to increase hardness 50ppm, 25 Lbs/200ppm.

Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride. See package for instructions. Dosage: 2, 000 gallons: 1.
1. Clorox
#ad
4 lb, Clorox Pool&Spa 12204CLX Calcium Hardness Increaser, White
#adClorox #ad - Ideal for plaster pools and soft water areas. Prevents pool surface damage. Prevents corrosion, etching, and staining. Increases low Total Hardness levels in swimming pool water. For best results, use with the Clorox Pool app. Power source Type: Manual.More information #ad
Brand | Clorox #ad |
Manufacturer | Clorox® Pool&Spa™ #ad |
Height | 11.5 Inches |
Length | 4.4 Inches |
Weight | 4 Pounds |
Width | 10 Inches |
Part Number | 12204CLX |
Model | 12204CLX |
More information #ad
2. MAV AquaDoc
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AquaDoc | Spa Calcium Hardness Increaser Hot Tub Owners Rely on, Spa Calcium Increaser & Hot Tub water hardener Spa Chemicals, Calcium Increaser Spa Hardness Increaser & Calcium Booster for Hot Tubs
#adMAV AquaDoc #ad - Our spa hardness increaser easily works to raise your Calcium levels by 10ppm increments or more. How it works - aquadoc's hot tub calcium hardness increaser works to raise your water's hardness level to ensure properly balanced hot tub water. Always have a hot tub calcium booster ready and waiting.Our spa calcium hardness increaser is vital to ensuring proper water hardness levels in your hot tub. Avoid corrosion, etching, and staining - aquadoc's professional Grade Hot Tub Calcium increaser is your best defense against soft water in your hot tub or spa.
More information #ad
Aquadoc's calcium Booster gets your hardness up. Guard calcium levels from decreasing too low with our spa Calcium booster for hot tubs. Make balancing your water easier & more cost effective with AquaDoc's calcium hardness increaser. Easy to use, add proper amount of increaser while equipment is on. The hardness increaser hot tub owners love - when it comes to Spa Chemicals calcium hardness increaser is a must have. 3 after determining hardness level goal, wait 20 minutes, then retest water. 4 run filter for 1 - 2 hours, made in the usa - 1 check your calcium levels, 2 1 ounce of AquaDoc's Calcium increaser will boost water's hardness level by 10ppm. Without hot tub chemicals calcium hardness can become unbalanced.
Brand | MAV AquaDoc #ad |
More information #ad
3. Baqua Spa
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14 oz, BAQUA Spa 88825 Calcium Hardness Increaser Spa and Hot Tub Balancer
#adBaqua Spa #ad - Includes: one 14-oz container of BAQUA Spa Calcium Hardness Increaser. Compatibility: Works with all biguanide sanitizer systems. Use: part of baqua spa's bromine-free and chlorine-free maintenance product line.More information #ad
Benefits: raises spa water to the recommended level of calcium hardness. Features: Bromine and chlorine free.Brand | Baqua Spa #ad |
Manufacturer | Innovative Water Care #ad |
Height | 2.44 Inches |
Length | 2.44 Inches |
Weight | 1 Pounds |
Width | 6.2 Inches |
Part Number | 88825 |
Model | 88825 |
More information #ad
4. SpaChoice
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2-Pack, Spa Choice 472-3-3061-02 Increase Calcium Spa Chemical, 1-Quart
#adSpaChoice #ad - Low hardness will etch plaster and corrode spa equipment. The ideal hardness level is 200-400 ppm parts per million. Spa choice increase calcium is used to increase calcium hardness in spas and hot tubs in areas with low levels of hardness.More information #ad
Downloadable user guide Available Under Product Information: Technical Specifications.Brand | SpaChoice #ad |
Manufacturer | Spa Choice #ad |
Height | 10 Inches |
Length | 6 Inches |
Weight | 4.5 Pounds |
Width | 3 Inches |
Part Number | 472-3-3061-02 |
Model | 472-3-3061-02 |
More information #ad
5. Spa Essentials
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12-Ounce, Spa Essentials 32534000 Calcium Hardness Increaser Granules for Spas and Hot Tubs
#adSpa Essentials #ad - Helps prevent corrosion Of Spa Equipment And Surfaces. Increases calcium Hardness Level In Spa Water. Easy to Use. No assembly Required.More information #ad
Brand | Spa Essentials #ad |
Manufacturer | Robelle Industries #ad |
Height | 8 Inches |
Length | 3 Inches |
Weight | 0.75 Pounds |
Width | 3 Inches |
Part Number | 32534000 |
Model | 32534000 |
Warranty | Returns are not accepted on opened or used products and are subject to a 20% restocking fee |
More information #ad
6. Puri Tech
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Puri Tech Pool Chemicals Calcium Hardness Increaser Plus for Pools & Spas Increases Calcium Hardness Levels 5lb
#adPuri Tech #ad - Raises calcium in swimming pool water. Calcium hardness level prevents foaming, equipment and surface erosion and scaling. 10, 25 lbs/200ppm.Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride. 5, 12. 5 lbs/200ppm. See package for instructions.
More information #ad
Dosage: 2, 000 gallons: 6. 25 lbs to increase hardness 50ppm, 6. 25 lbs/200ppm. 20, 12. 5 lbs/100ppm, 25 lbs/100ppm, 000 gallons: 1. 5 lbs to increase hardness 50ppm, 000 Gallons: 3 Lbs to increase hardness 50ppm, 6. 25 lbs/100ppm, 3 lbs/100ppm, 000 Gallons: 105 lbs to increase hardness 50ppm, 50 Lbs/200ppm.Brand | Puri Tech #ad |
Manufacturer | Puri Tech #ad |
Height | 6 Inches |
Length | 12 Inches |
Width | 6 Inches |
Part Number | PCC |
Model | PCC |
More information #ad
7. SpaGuard
#ad
12 Ounce, SpaGuard Spa Calcium Hardness Increaser
#adSpaGuard #ad - Prevents etching of plaster due to low calcium hardness. Prevents corrosion of equipment due to low calcium hardness. 1 tbs. Per 100 gallons raises calcium hardness 25ppm.More information #ad
Brand | SpaGuard #ad |
Manufacturer | SpaGuard #ad |
Weight | 0.75 Pounds |
Part Number | 42257BIO |
Model | BIO42257 |
Warranty | Returns are not accepted on opened or used items and are subject to a 20% restocking fee. |
More information #ad
8. Puri Tech
#ad
Puri Tech Pool Chemicals 50 lb Calcium Hardness Increaser Plus for Swimming Pools & Spas Increases Calcium Hardness Levels Prevents Staining on Surfaces
#adPuri Tech #ad - Raises calcium in swimming pool water. Calcium hardness level prevents foaming, equipment and surface erosion and scaling. See package for instructions.5, 000 gallons: 105 lbs to increase hardness 50ppm, 50 Lbs/200ppm. Dosage: 2, 25 lbs/200ppm. Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride.
More information #ad
10, 12. 5 lbs/100ppm, 3 lbs/100ppm, 6. 25 lbs/200ppm. 20, 000 gallons: 6. 25 lbs to increase hardness 50ppm, 25 lbs/100ppm, 6. 25 lbs/100ppm, 000 gallons: 1. 5 lbs to increase hardness 50ppm, 000 gallons: 3 lbs to increase hardness 50ppm, 12. 5 lbs/200ppm.Brand | Puri Tech #ad |
Manufacturer | Puri Tech #ad |
Height | 9 Inches |
Length | 19 Inches |
Width | 13 Inches |
More information #ad
9. Puri Tech
#ad
Puri Tech Pool Chemicals 10 lb Calcium Hardness Increaser Plus for Swimming Pools & Spas Increases Calcium Hardness Levels Prevents Staining on Surfaces
#adPuri Tech #ad - 10, 12. 5 lbs/100ppm, 25 lbs/100ppm, 6. 25 lbs/100ppm, 3 lbs/100ppm, 000 gallons: 3 lbs to increase hardness 50ppm, 6.25 lbs/200ppm.20, 000 gallons: 1. 5 lbs to increase hardness 50ppm, 000 Gallons: 6. 25 lbs to increase hardness 50ppm, 50 Lbs/200ppm. 5, 000 gallons: 105 lbs to increase hardness 50ppm, 25 Lbs/200ppm.
More information #ad
Raises calcium in swimming pool water. Calcium hardness level prevents foaming, equipment and surface erosion and scaling. See package for instructions. Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride. Dosage: 2, 12. 5 lbs/200ppm.Brand | Puri Tech #ad |
Manufacturer | Puri Tech #ad |
Part Number | PCC |
Model | PCC |
More information #ad
10. Puri Tech
#ad
Puri Tech Pool Chemicals 25 lb Calcium Hardness Increaser Plus for Swimming Pools & Spas Increases Calcium Hardness Levels Prevents Staining on Surfaces
#adPuri Tech #ad - Raises calcium in swimming pool water. Calcium hardness level prevents foaming, equipment and surface erosion and scaling. 5, 50 lbs/200ppm.Brand new packaging: all puri Tech Chemicals now come in resealable bags for easy storage! Active ingredients: Calcium Chloride. See package for instructions. Dosage: 2, 000 gallons: 1.
More information #ad
5 lbs to increase hardness 50ppm, 000 gallons: 6. 25 lbs to increase hardness 50ppm, 000 gallons: 105 lbs to increase hardness 50ppm, 12. 5 lbs/100ppm, 25 lbs/100ppm, 3 lbs/100ppm, 000 gallons: 3 Lbs to increase hardness 50ppm, 25 Lbs/200ppm.20, 12. 5 lbs/200ppm. 10, 6. 25 lbs/100ppm, 6. 25 lbs/200ppm.Brand | Puri Tech #ad |
Manufacturer | Puri Tech #ad |
Part Number | PCC |
Model | PCC |
More information #ad