nudis are alright so long as you can identify and then provide the food source
finding info is hard
http://www.teara.govt.nz/EarthSeaAndSky ... lfish/3/en
i plug nz nudibranch species into google then start searching
most can be found on their food source i just sit and observe to see if they are feeding
longest i have had one is 12 months, still alive but released, don't know life span sorry