charge - discharge battery cycle questions

Alkaline-Hater

skyrc mc3000 charger
nimh batteries
2450 mah capacity

Question 1:

I would like to know what to set the capacity to when doing automatic charge - discharge cycles. Normally, when just charging I add approx. 20% to the stated capacity. So, in this case I am using 2900 mah as the target capacity. However, when doing a discharge, I only put in 2400 as the closest approximation. This brings me to the point of my question: how can I do a charge - discharge cycle if the capacity mah need to be different? AFAIK, I can only choose one capacity amount. There are safety mechanisms built into a discharge cycle, but concerned that the battery being discharged at a 2900mah capacity rating may be too much. Likewise, I do not want to charge the battery at only its stated capacity of approx. 2400.

Question 2:

As a battery ages, should I lower the mah capacity target? Meaning, the stated capacity on a label may be 2450mah, but when discharged the actual produced capacity is lower than this. For example, it could be 2372mah, or 2247mah, etc. Should I then make sure to charge these batteries based on these new capacity amounts? So, in the case of a battery reading 2247mah, should the target capacity be changed from 2900mah to 2700mah?

Thanks!