The proper recommendation is to get your soil/water tested for pond purposes. Then you will know what if any limiting factor is present and can deal with it correctly. Then if your goals , as noted in the archive, are consistent with needing extra fertility you can decide on that option. Fertilization is a tool to be used in the proper situation with a full understanding of its application to your pond and goals. I would hate for any PB forum member to take a blanket fertilization recommendation and then call me to report a dense plankton bloom followed by a fish kill. Knowledge first then proper application of that knowledge to your situation and goals.