Marquis Vector21 Owner's Manual page 57

Total Alkalinity
Alkalinity acts as a buffer to prevent the pH from changing as other sub-
stances are added to the water. Stability of the pH is directly related to the
alkalinity. The alkalinity should be between 80 - 140 ppm. Alkalinity below
80 ppm makes it difficult to stabilize the pH. Alkalinity above 140 ppm may
increase the pH and cause cloudy water, scaling, and decreased efficiency
of the sanitizer.
NOTE: Alkalinity Increaser, pH Increaser and Alkalinity & pH Decreaser will
affect both the pH and alkalinity. Generally, smaller additions will change the
pH and have a very minor effect on the alkalinity. Larger additions will also af-
fect the pH, but will have a much greater effect on the alkalinity. (Example: If
the pH is very high and the alkalinity is within range, adding just a few smaller
doses of pH and Alkalinity Decreaser instead of one large dose will reduce
the pH with little effect on the alkalinity.)
Calcium Hardness
Do not use soft water in your vessel. It is critical to have calcium in your
water. The ideal range of calcium is between 200 – 300 ppm. The calcium
hardness is normally adjusted when filling or refilling after draining the vessel.
High calcium levels can cause scale buildup on vessel surfaces and equip-
ment. Your vessel can be protected against high calcium by using Metal
& Stain Remover per the directions on the container. Low calcium levels
can cause vessel water to become highly corrosive and damaging to the
equipment components and plumbing. To raise calcium levels, use Calcium
Hardness Increaser.
Balance
When initially filling or refilling your vessel, follow these steps to achieve
proper water balance.
Important! Always follow instructions on the chemical container when add-
ing chemicals.
1. Test the vessel water using a test strip or test kit. Determine the pH and
alkalinity of the water.
2. If adjustments are needed for the pH and/or alkalinity, always balance
the alkalinity before balancing the pH. The product(s) you should use to
adjust pH and/or alkalinity are pH Increaser, Alkalinity Increaser or pH &
Alkalinity Decreaser. Make any additions per the directions on the bottle
and then test and repeat if necessary until all readings are in the desired
range.
3. Increase the calcium hardness if necessary.
VECTOR21 SPA CARE GUIDE
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