I'm thinking i missed one or more of the feeding solutions for the servant mind. Do I get any kind of reward for bringing him back to health or is it just for xp/fun? Also, where are the solutions? Thanks.

Feeding servant minds can have variety of effects depending of the mind in question (information, disabpling defences, opening doors you can't open yourself etc.). Feeding and killing some of them are also faction quests (and as shaper loyalist you would feed as many as you can, at least those who have remainded loyal).

There are 6 servant mind nutrients and 7 minds that require it so you will have to choose who not to feed.

Mind Nutrients can be found inside Ellhrah's Keep, Hill of Jars, Kazg, Holding 2, South Workshop and Holding Cells.