Hey, so I ordered Brightwell Aquatics Magnesion-P a little while ago and havent needed to use it, prior to this just used liquid magnesium from Petco. My magnesium is currently testing at 1230 and it's been like 1350 but didn't test for two weeks and it fell. If I want to get it back up to 1350-1400 according to brs calculator. I have 65 gallons of volume and I just put in 1350 to get it up to and it's saying 340.91 grams( which is half of the bottle of powder). Now on the Brightwell bottle, it says (Amt to raise) x (tank volume) / 64 = Amt (grams) which is 121.85 grams. Also on the bottle, it says every 3.5 grams needs 32 oz of water. I am extremely confused anybody with experience with this product could weigh in and give me insight on what I should do, please.