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Without hot tub chemicals calcium hardness can become unbalanced. Make balancing your water easier & more cost effective with AquaDoc's calcium hardness increaser.
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. 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. Easy to use, 2 1 ounce of aquadoc's calcium increaser will boost water's hardness level by 10ppm.



1. Clorox Pool&Spa
#ad
Clorox Pool&Spa 12204CLX Calcium Hardness Increaser, White, 4 lb
#adClorox Pool&Spa #ad - Ideal for plaster pools and soft water areas. Power source Type: Manual. Prevents pool surface damage. Increases low Total Hardness levels in swimming pool water. Prevents corrosion, etching, and staining. For best results, use with the Clorox Pool app.More information #ad
Brand | Clorox Pool&Spa #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. Pool Mate
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25-Pound, Pool Mate 1-2825 Calcium Increaser for Swimming Pools
#adPool Mate #ad - Prevents the staining or etching of your pool's surface. Ideal calcium hardness range 200 - 400ppm. Low calcium hardness level can cause corrosive water. Increases Water Hardness.More information #ad
Brand | Pool Mate #ad |
Manufacturer | Robelle Industries #ad |
Height | 11 Inches |
Length | 10.25 Inches |
Weight | 25 Pounds |
Width | 10.25 Inches |
Part Number | 1-2825 |
Model | 1-2825 |
More information #ad
3. 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 | Bioguard #ad |
Weight | 0.75 Pounds |
Part Number | 42257BIO |
Model | BIO42257 |
More information #ad
4. Robelle
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Robelle 2816B Calcium Hardness Increaser for Swimming Pools, 16 Pounds
#adRobelle #ad - Prevents the staining or etching of your pool's surface. Ideal calcium hardness range 200 - 400ppm. Low calcium hardness level can cause corrosive water. Increases Water Hardness.More information #ad
Brand | Robelle #ad |
Manufacturer | Robelle #ad |
Height | 12 Inches |
Length | 12 Inches |
Weight | 16 Pounds |
Width | 12 Inches |
Part Number | 2808B-02 |
Model | 2816B |
More information #ad
5. Quality Producer Direct
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Calcium Hardness Increaser 1 Gallon Calcium Chloride Powder for Pools & Hot Tubs
#adQuality Producer Direct #ad - Calcium chloride anhydrous Powder Increases Total Hardness of Pool Water. Manufactured in the USA. Used to prevent Corrosion in Pools & Hot Tubs. Great value: 1 gallon of Calcium Chloride Powder. Lab-tested & Certified.More information #ad
Brand | Quality Producer Direct #ad |
Manufacturer | Quality Producer Direct #ad |
Height | 7.5 Inches |
Length | 7.47 Inches |
Width | 7.47 Inches |
More information #ad
6. MAV AquaDoc
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Spa Calcium Increaser & Hot Tub Water Hardener Spa Chemicals, AquaDoc | Spa Calcium Hardness Increaser Hot Tub Owners Rely on, Calcium Increaser Spa Hardness Increaser & Calcium Booster for Hot Tubs
#adMAV AquaDoc #ad - Guard calcium levels from decreasing too low with our spa Calcium booster for hot tubs. 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. 3 after determining hardness level goal, made in the USA - 1 Check your calcium levels, wait 20 minutes, add proper amount of increaser while equipment is on.Without hot tub chemicals calcium hardness can become unbalanced. Make balancing your water easier & more cost effective with AquaDoc's calcium hardness increaser.
More information #ad
Our spa hardness increaser easily works to raise your Calcium levels by 10ppm increments or more. Always have a hot tub calcium booster ready and waiting. Aquadoc's calcium Booster gets your hardness up. 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. 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. Easy to use, 2 1 ounce of aquadoc's calcium increaser will boost water's hardness level by 10ppm.
Brand | MAV AquaDoc #ad |
Manufacturer | MAV AquaDoc #ad |
Weight | 0.88 Pounds |
More information #ad
7. Spa Essentials
#ad
Spa Essentials 32534000 Calcium Hardness Increaser Granules for Spas and Hot Tubs, 12-Ounce
#adSpa Essentials #ad - No assembly Required. Helps prevent corrosion Of Spa Equipment And Surfaces. Increases calcium Hardness Level In Spa Water. Easy to Use.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 |
More information #ad
8. LEISURE POOL & SPA SUPPLY INC. LP
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Leisure Pool 50 lb. Calcium Hardness Increaser Calcium Chloride
#adLEISURE POOL & SPA SUPPLY INC. LP #ad - Dosing instructions: 1. 1 lb. Other uses: ice melt, dust control, concrete acceLERATOR. Calcium chloride dry granules commonly known as Calcium Hardness Increaser, will raise calcium hardness levels in commercial and residential swimming pools and spas.More information #ad
Per 10, 000 gallons will raise CH levels by 10 ppm.Brand | LEISURE POOL & SPA SUPPLY INC. LP #ad |
Manufacturer | Leisure Pool & Spa Supply, Inc. #ad |
Height | 15 Inches |
Length | 12 Inches |
Width | 12 Inches |
Model | C23444-PL |
More information #ad
9. Doheny's
#ad
Doheny's Calcium Plus | Raise Your Calcium Hardness Level | Pro-Grade Granular/Flake Calcium Chloride | Low Calcium Hardness Levels Lead to Corrosion & Staining On Pool Surfaces and Fixtures | 25 LB
#adDoheny's #ad - Benefits of doheny's calcium Plus: Balanced Calcium Hardness levels reduce equipment corrosion and staining in your swimming pool. Pool calcium hardness increaser: Proper Calcium Hardness levels increase the effectiveness of your other pool chemicals.More information #ad
Calcium hardness increaser for Swimming Pools: Instantly increase the calcium hardness levels in your swimming pool. Packaging: 5-lb ready-to-use pouch or 25-pound bucket available. Ingredients: made of 100% Granular Calcium Chloride.Brand | Doheny's #ad |
Manufacturer | Doheny's #ad |
Weight | 25 Pounds |
More information #ad