Need Quick Advice Re "Top-up" of Medication

[Barracuda]

When you change already medicated water in the tank, do you add the full dose to the tank according to the tank capacity (eg. for med 1ml per 10l in a 100l tank, add 10ml med), or do you add the amount for new water (eg. add 20l water add 2ml med). So in summary add original full dose or add the partial dose according to the amount of new water?
Hope this makes sense...
Thanks

[ILLUSN]

depending on the med, most waterlife products are designed to build on themselves over several days, so if you change water inbetween days 1 and 2 you'll need to add enough med to make up for what you took out, + the day 2 dose.

other meds like triple sulfa and salt you dont need to worry