Here's a Calculation I did a while back, my kalk cost is even less than the $40 per year since I am only using 1 tsp per gallon right now.
Kalkwasser... the max you mix is 2 teaspoon of kalk powder for every 1 gallon of water.
16oz per container converts to 96 teaspoons in each container.
96/2 = 48 gallons of limewater per container
48 gallons per container x 4 containers = 192 gallons
Top off container holds approx 15 gallons at a time, and we'll say my tank exhaust this supply weekly.
so 192 gallons/15 gallons per week = 12.8 or basically 3 months worth of kalk powder for $10
So I would be talking $40 a year to run my system with kalk... IF I mix it to the 2 tsp potency.
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ESV B-Ionics costs $27.99 or around $30.00 with tax, for the 2 gallon set (1 gallon each part).
1 U.S. gallon = 128 oz.
128 oz. x 2 (# of containers in set) = 256 ounces in the set.
1 oz. = 29.5735296 ml
256 oz x 29.57 ml = 7,570.82 ml (in the set)
I currently dose 30ml of each part per night.
30 ml x 2 (because there are 2 parts ) = 60 ml per day
7,570.82 ml/60 ml = 126.18 days or basically 4 months.
So I'm talking a cost of $120 per year to dose with ESV 2-Part... IF my daily draw NEVER increases.
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Kalk: $40 per year
ESV 2-Part: $120 per year