View Full Version : Chem calculator...something doesnt seem right??

09/28/2006, 06:21 PM
Ok...I may be losing it but here we go.

I want to bump my calcium in my Instant Ocean from 350 to 420. The calculator tells me to use .9g per gallon of dow flake.

I've figured out that there is .254g of calcium in .9g of calcium chloride. What is the math that shows this will add 70ppm per gallon??

I only ask because I have tried this and it didnt seem to raise the calcium like I thought it should.?? thanks

09/28/2006, 06:26 PM
I think its because your volume input is off. You cant put in 55 gallons for example. You have to minus your rocks and sand. After doing that your water volume is a lot less.

09/28/2006, 06:37 PM
Never mind......I the calculator is right. My brain is off. I just figured it out.

Randy Holmes-Farley
09/29/2006, 06:01 AM

It is a great tool!

Happy reefing. :)

09/29/2006, 06:30 PM
If you are still interested in the math...

mg/lt aprox= ppm

so .254g = 254mg/gal = 254/3.7856 mg/lt = 67 ppm. so aprox 70 ppm after calculator's rounding error.

To reduce the rounding errors use 1000 gal as the volume and you will get more digits on the 0.9 g / gal