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Our spa calcium hardness increaser is vital to ensuring proper water hardness levels in your hot tub. 4 run filter for 1 - 2 hours, then retest water. The hardness increaser hot tub owners love - when it comes to Spa Chemicals calcium hardness increaser is a must have.
Always have a hot tub calcium booster ready and waiting. 3 after determining hardness level goal, Made in the USA - 1 Check your calcium levels, add proper amount of increaser while equipment is on. 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. 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.





1. SpaGuard
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12 Ounce, SpaGuard Spa Calcium Hardness Increaser
#adSpaGuard #ad - 1 tbs. Per 100 gallons raises calcium hardness 25ppm. Prevents etching of plaster due to low calcium hardness. Prevents corrosion of equipment due to low calcium hardness.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
2. MAV AquaDoc
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Calcium Increaser Spa Hardness Increaser & Calcium Booster for Hot Tubs, Spa Calcium Increaser & Hot Tub water hardener Spa Chemicals, AquaDoc | Spa Calcium Hardness Increaser Hot Tub Owners Rely on
#adMAV AquaDoc #ad - Without hot tub chemicals calcium hardness can become unbalanced. Our spa hardness increaser easily works to raise your Calcium levels by 10ppm increments or more. Aquadoc's calcium Booster gets your hardness up. Guard calcium levels from decreasing too low with our spa Calcium booster for hot tubs.Our spa calcium hardness increaser is vital to ensuring proper water hardness levels in your hot tub. 4 run filter for 1 - 2 hours, then retest water. The hardness increaser hot tub owners love - when it comes to Spa Chemicals calcium hardness increaser is a must have.
More information #ad
Make balancing your water easier & more cost effective with AquaDoc's calcium hardness increaser. Easy to use, wait 20 minutes, 2 1 ounce of aquadoc's calcium increaser will boost water's hardness level by 10ppm. Always have a hot tub calcium booster ready and waiting. 3 after determining hardness level goal, Made in the USA - 1 Check your calcium levels, add proper amount of increaser while equipment is on. 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. 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.
Brand | MAV AquaDoc #ad |
More information #ad
3. LEISURE TIME
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Leisure Time CB Calcium Booster Balancer for Spas and Hot Tubs, 32 fl oz
#adLEISURE TIME #ad - Benefits: raises water hardness to maintain a level of hardness between 150-400 ppm. Compatible with chlorine, bromine, ozone and biguanide sanitizers. Use: one ounce increases hardness 7 ppm in 500 gallons of water.More information #ad
Features: prevents corrosion and foam; Part of Leisure Time's Simple Spa Care program. Includes: one 32-oz bottle of Leisure Time Calcium Booster. Prevents corrosion. Compatibility: Compatible with chlorine, ozone, bromine, and biguanide sanitizers. One ounce increases hardness 7 ppm in 500 gallons of water.Brand | LEISURE TIME #ad |
Manufacturer | Leisure Time #ad |
Height | 9.5 Inches |
Length | 3.12 Inches |
Weight | 2.58 Pounds |
Width | 3.12 Inches |
Part Number | CB |
Model | CB |
More information #ad
4. Spa Essentials
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Spa Essentials 32534000 Calcium Hardness Increaser Granules for Spas and Hot Tubs, 12-Ounce
#adSpa Essentials #ad - No assembly Required. Easy to Use. Helps prevent corrosion Of Spa Equipment And Surfaces. Increases calcium Hardness Level In Spa Water.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
5. PureSpa
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SpaPure Calcium Hardness Increaser 16oz
#adPureSpa #ad - Protect your spa equipment and bather comfort. Ensure water won't become corrosive. Fast acting liquid calcium hardness balancer.More information #ad
Brand | PureSpa #ad |
Manufacturer | Haviland #ad |
Part Number | SPA2729CS20B6 |
More information #ad
6. Baqua Spa
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BAQUA Spa 88825 Calcium Hardness Increaser Spa and Hot Tub Balancer, 14 oz
#adBaqua Spa #ad - Features: Bromine and chlorine free. Compatibility: Works with all biguanide sanitizer systems. Benefits: raises spa water to the recommended level of calcium hardness.More information #ad
Includes: one 14-oz container of BAQUA Spa Calcium Hardness Increaser. Use: part of baqua spa's bromine-free and chlorine-free maintenance product line.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
7. Clorox
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White, Clorox Pool&Spa 12204CLX Calcium Hardness Increaser, 4 lb
#adClorox #ad - Ideal for plaster pools and soft water areas. For best results, use with the Clorox Pool app. Prevents corrosion, etching, and staining. Prevents pool surface damage. Increases low Total Hardness levels in swimming pool water. 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