Hey brother,
Correct, you'll need BAC water to reconstitute the HCG. When adding 2mL of BAC the numbered markers on your insulin needle (assuming you're using a 1mL slin pin) will reflect the following:
10 - 250iu
20 - 500iu
30 - 750iu
40 - 1000iu
50 - 1250iu
60 - 1500iu
70 -1750iu
80 - 2000iu
90 - 2250iu
100 - 2500iu
So if your desired dosage is 250iu you'd draw to the "10" marker.
Here is a helpful site you can use for a visual aid:
https://peptidecalc.com
Let me know if you have any other questions.
AJ