I think the Water Parade happens every night with weather permitting. Spectro and Wishes have a schedule, and do not happen every night. We will be going at the end of this month and Wishes is not scheduled for some of our stay so I know for sure it's not every night in April.
You can find the park hours and parade/show schedules under the Theme Parks section of this site. Here is the link to the main hours page http://www.wdwinfo.com/wdwinfo/hours.htm