Help me figure out how to dose alk please

[DrewBrees713]

Ok so Id like to dose baking soda for alk and i know how to use the reef calculator. It tell me i need 2g of baking soda but didnt say in how much water. And do i dump it all at once into the tank? Thanks

 

[Sierra_Bravo]

I know this isn't exactly what you asked for, but it's good info.

You should convert it first to sodium carbonate, especially if your pH is low. Follow Randy's part one recipe for an alk solution: https://www.advancedaquarist.com/2004/4/chemistry#section-3

The Alkalinity Part
Spread baking soda (594 grams or about 2 1/4 cups) on a baking tray and heat in an ordinary oven at 300 °F for 1 hour to drive off water and carbon dioxide. Dissolve the residual solid in enough water to make 1 gallon total. This dissolution may require a fair amount of mixing. Warming it speeds the dissolution process. This solution will contain about 1,900 meq/L of alkalinity (5,300 dKH). I prefer to use baked baking soda rather than washing soda in this recipe as baking soda from a grocery store is always food grade, while washing soda may not have the same purity requirements. Arm & Hammer brand is a fine choice.

Then use this great calculator to determine your dosing quantity: http://reef.diesyst.com/chemcalc/chemcalc.html

How much you are trying to raise your dKH will be the consideration for how fast you put it in. A lot of folks recommend no more than .5 dKH per day. If you are just trying to raise it .1 or .2, no problem doing it at once. Otherwise, it's better to add a little bit at a time. Add to an area of high flow or your sump.

 

[DrewBrees713]

I read the article some time ago. I will be adding the bs slowly no more than .5/day. i guess it doesnt matter how much water to dilute it in, i suppose.

 

[Sierra_Bravo]

I read the article some time ago. I will be adding the crap slowly no more than .5/day. i guess it doesnt matter how much water to dilute it in, i suppose.

He (Randy) stated 2 1/4 cups baking soda, converted by heating in the oven, and add to a gallon of water.

 

[DrewBrees713]

Read that too but how much of the solution to add? The calculator only has the dry solution in grams.

 

[Sierra_Bravo]

Read that too but how much of the solution to add? The calculator only has the dry solution in grams.

Maybe this will help. This is an example in 100 gallons of water of raising your dKH from an existing 7.5 to 8.0. You would need 35.7 ml, which is equal to 1.2 fluid oz or 7.1 teaspoons, of the above solution.

 

[DrewBrees713]

Sorry im a little confused. I just want to know dor example if i need to dose x amount of dry solution such as baking soda. How much water do i need to add it to thanks

 

[Sierra_Bravo]

Sorry im a little confused. I just want to know dor example if i need to dose x amount of dry solution such as baking soda. How much water do i need to add it to thanks

Let's start with this:

1. What is the volume of water in the tank you want to dose?
2. What is your current alkalinity level?
   
3. What do you want your alkalinity level to be?

 

[DrewBrees713]

I have a 25g cube. Current alk is 8 would like to be at 9dkh. And i like to use non baked baking soda thanks!

 

[Sierra_Bravo]

I have a 25g cube. Current alk is 8 would like to be at 9dkh. And i like to use non baked baking soda thanks!

OK. I understand what you are asking now (finally - I'm sometimes a bit slow ). That calculator has baking soda as an option. To raise 25 gallons 8 dKH to 9 dKH you need 2.8 grams of non-baked baking soda. You could dissolve 2.8 grams into say, 40ml of water or whatever amount you choose, dose it all and you are there. You are right that it doesn't matter how much technically. Put it in too much water and you dilute the affect by changing the volume of water in your tank. Too little and 2.8 grams won't dissolve in it (need at least 30 ml for that amount to dissolve).

Or if you wanted to make a gallon of solution to keep on hand to do the same thing:

A gallon is 3785ml.

3785ml/40ml = 94.625
94.625*2.8g = 264.95g

So 265 grams of baking soda into a gallon of RODI would yield a solution that would raise your tank 1 dKH if you added 40ml of it to your tank. That's if my math is right. . .

265g of baking soda = 1.15 cups.

Does that get you what you were looking for?

 

[DrewBrees713]

Yes, Exactly what i was looking for. Can i also dilute cal in 40ml of water ? Would that be enough water to dilute it in?

 

[Sierra_Bravo]

Yes, Exactly what i was looking for. Can i also dilute cal in 40ml of water ? Would that be enough water to dilute it in?

Yes, up to 29g of calcium chloride will dissolve in 40ml of water at room temperature. But you have to do it separately, not in the same solution. Use that calculator the same way to determine how much you need to raise it where you want it.

 

[DrewBrees713]

Youre awesome. Thank you for taking the time out to answer my stupid questions.