Pond Boss Forums MANAGING AN EXISTING POND Fertilization Organic Fertilizer or not?

The only way to approach the issue is to determine what is the limiting factor. In ponds it is usually not low N , but is often low phosphorous (P).
A water and soil test would be wise and inexpensive.

In many southern ponds low alkalinity is the limiting factor. Also there are different fertilizer formulations and most pond types are low or 0 N and K and high P.