Juan, that doesn't sound right. I don't know your total volume, but 2.4 tsp might be alright for a very small nano tank.
With the BRS calculator, assuming you cooked the baking soda, you want to pick "2 Part Alkalinity (soda ash)." The other consideration is that you don't want to raise alkalinity more than 1 dKH per day. So go slow in raising you alkalinity.
EDIT TO ADD: I think I see what you did....dry soda ash. I just assumed you made up the alkalinity solution of 2 1/4 cups of cooked baking soda made up to one gallon with RO/DI water.
Paul I did the calculation for 80 gal of total water volume and yes I did baked the baking soda, 2 1/4 cups of b.s. at 300 degree for 1 hour and then RO/DI water to complete a gallon of total solution.
I don't have any dosing system and i can't afford to buy one now I guest I'll make a simple dripping one for now.
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