So now I have a new recipe. I'll need distilled water, KNO3, CSM+B and Iron 13% EDTA. I'll need a container to mix it all in and if I make up 1000ml I know I'll need 80g of KNO3 and 30g of the CSM+B. I know this because this recipe has the same concentration of those components as the original solution I'll be adding to.
What I don't know right now is precisely how much of the old solution I have left. I'll pour out the solution into a container with trusted graduations and find … let's say … between 350ml and 400ml. If that's the best I can do with what I have I'll have to start with 350ml and discard the rest. Still a waste, but nothing to cry about. Now to open Excel (oops I'm on my home PC I have to use Open Office Calc) and load up MakeupSol.xls. and enter in the info.
You'll need to download and extract MakupSol.xls from the zip
View attachment 1820.
Four tables … Ok? What to enter and where?
First the main quantities:
1.In the cell labeled 'Recipe volume' enter the base volume used to create the recipe in StockSol.
2.In the cell labeled 'Volume remaining' enter the volume you have left or, in this case, you are going to keep.
3.In the cell labeled 'Makeup volume' enter the amount of makeup solution water you plan to use.
Next you need to define the recipe:
Here you have the first opportunity to enter the names of the components in the recipe. Not necessary but it could help to keep track of the process. These cells can be anything or left blank with no effect. In the 'Grams' column enter the values in grams for the recipe you created in StockSol.
Next you need to define the components of the recipe that are included in the remainder of the existing solution:
This is done by placing a 1 in the column labeled 'In sol. Now (1/0)'. Notice that a 0 is in the column for the Iron. There is no Iron yet and if you placed a 1 there, the calculation for the amount needed to correct the existing solution for the absence of that component would not be made.
That's it. You're done. Check out your makeup solution.
Just take the values from the darker blue column labeled 'Total grams in makeup sol' for each of the components, add them to the water measured out for the makeup solution. Mix thoroughly and then add the completed makeup solution to the remaining existing solution. Your new stock solution is ready to dose. You should add two or three drops of anti-fungal medication to the mix to insure it doesn't get fungal growth if your solution includes Iron.
Well, That's all … right? …. Nope, there's those zero's in the '% increase' column. Wouldn't it be nice to just alter the concentrations of an existing solution and know exactly what's in it when you were done? … sure it would.
Next time … Stay tuned.
Pat