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bavass
03-21-2011, 22:10
the formula 0.002x50x25=2.5 teaspoons into the top-off water for calcium I dont quiet understand how much top off water is this for? I have two five gallon water jugs that I fill for top off water. How would I figure out how much Calcium, Alkalinty, magnesium, strotium etc. would I add to 5 gallons so that it will benefit my reef tank when I add my top off water? I hope that question makes sense?

Tech Support MS
03-22-2011, 09:43
The formula is for how much you would like to raise your calcium or how much you will need to maintain it over a period of time before needing more top off water. So lets say that you use 5 gallons of top off your 200L system every week and that your calcium is depleted by 25 mg/l over that same period. You would use the formula m=vc/400 which would look like this----- 200x25/400=m. m will equal 12.5g of Reef Advantage Calcium.

The formula for magnesium is pretty much the same. g=vm/80 (g=grams to add to top off water, v=volume of tank in liters, m=amount to raise magnesium in mg/L). For example, if you want to raise magnesium by 10 mg/L in a 200 liter tank, then you would add (200x10)/80=25 g into the top-off water. [For reference: 1 gallon*=3.8 liters, 5 g=1 teaspoon*].

As is the formula for strontium and alkalinity.
Strontium - m=vs/30 (m=grams to add to top off water, v=volume of tank in liters, s=amount to raise strontium in mg/L). For example, if you want to raise strontium by 6 mg/L in a 200 liter aquarium, then you would add (200x6)/30=40 g into the top-off water.

Alkalinity- t=0.05va (t=teaspoons to add to top off water, v=volume of tank in gallons, a=amount to raise alkalinity in meq/L). For example, if you want to raise your alkalinity by 1 meq/L in a 50 gallon tank, then you would add 0.05x50x1=2.5 teaspoons into the top-off water.

So, essentially, the amount of water you add the minerals to is not very important assuming you are not adding more than can be dissolved in that amount of water. You should not have any problems if you are using 10 gallons to top off with. I hope this has helped you out some, let us know if you have additional questions.