Response to Reciprocity Effects on APX25

You can't properly compensate for low-light reciprocity failure at the development stage. Reciprocity failure causes underexposure, coupled with an increase in contrast. Pulling the developer will decrease the contrast, but it'll also lose you a lot of shadow detail.
The best you can do, post-exposure, is to give slightly extended development using a compensating development technique, like two-bath, stand, or highly diluted development; or a slightly curtailed normal development, followed by a few minutes in a plain water bath without agitation. The latter technique allows the shadow and mid-tones to 'catch up' on the highlight density, taming the contrast without losing too much film speed.

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