Confused on how to use calculator-ALK

[Roccopaul]

So I’ve noticed that my alk over the period of a few weeks has been dropping regardless of water change of 5% weekly. It just hit 5.5 and a water change upped it to 6.5. I wanted to dose alk and looked of Randy’s 2 part.

so I have all the stuff I need to make everything. I understand the maintenance dosing of the 0.5ml/gallon. But…

when I check the calculator I’m not understanding how I’m supposed to dose before maintenance. Let’s use an example. If I’m at 6.5dkh and want to go to 7.5dhk with 49gallons , it wants me to use 3.5 grams, approx 0.7 tsp, or 0.1 oz. So does that mean.. I need to add 3.5grams to a gallon of water and dose that gallon? That doesn’t make sense to me.

Or does this mean that after mixing my solution of sodium carbonate , I only use 18.9ml of the solution which would be 3.5g?

 

[Randy Holmes-Farley Verified Community Expert]

So I’ve noticed that my alk over the period of a few weeks has been dropping regardless of water change of 5% weekly. It just hit 5.5 and a water change upped it to 6.5. I wanted to dose alk and looked of Randy’s 2 part.

so I have all the stuff I need to make everything. I understand the maintenance dosing of the 0.5ml/gallon. But…

when I check the calculator I’m not understanding how I’m supposed to dose before maintenance. Let’s use an example. If I’m at 6.5dkh and want to go to 7.5dhk with 49gallons , it wants me to use 3.5 grams, approx 0.7 tsp, or 0.1 oz. So does that mean.. I need to add 3.5grams to a gallon of water and dose that gallon? That doesn’t make sense to me.

Or does this mean that after mixing my solution of sodium carbonate , I only use 18.9ml of the solution which would be 3.5g?

If you made and entered my DIY Recipe #1 as detailed in my recipe article, it takes 35 mL of my liquid solution.

if you do not want to use that solution, then it says you need 3.5 grams of dry sodium carbonate, which you can dissolve in any amount of fresh water that actually dissolves it. It will take around 35 mL or less.

 

[Tray21]

My understanding is that the amount stated in the calculator, in this example the 3.5 grams, would be the total amount added. I dont have direct experience with this as I do weekly 20% water changes and have not yet had issues with alk. Maybe try increasing the volume of water you are changing weekly and see if that helps too. 5% seems a little low IMO.

 

[Roccopaul]

If you made and entered my DIY Recipe #1 as detailed in my recipe article, it takes 35 mL of my liquid solution.

if you do not want to use that solution, then it says you need 3.5 grams of dry sodium carbonate, which you can dissolve in any amount of fresh water that actually dissolves it. It will take around 35 mL or less.

Oh boy, I feel stupid now. I didn’t see your recipe in the list and automatically picked sodium bicarbonate thinking,”well that’s what’s in Randy’s recipe i just made”.

So that’s a total of 35ml at once to get right to 7.5. And not 35ml/gallon then I’ll go to the 0.5ml/gallon maintenance right?

 

[Randy Holmes-Farley Verified Community Expert]

Oh boy, I feel stupid now. I didn’t see your recipe in the list and automatically picked sodium bicarbonate thinking,”well that’s what’s in Randy’s recipe i just made”.

So that’s a total of 35ml at once to get right to 7.5. And not 35ml/gallon then I’ll go to the 0.5ml/gallon maintenance right?

Yes, but if you used sodium bicarbonate recipe (as opposed to sodium carbonate recipe), it needs 70 mL to get 1 dKH rise. The bicarbonate recipe is half as concentrated due to solubility.

For maintenance, unless you know the dKH per day needed, trial and error is the best way to figure it out.