Pond Boss Forums MANAGING AN EXISTING POND Fertilization Testing water clarity for fertilization

I'm back from Mexico and trying to catch up. Here are my thoughts on this fertilizer issue, based on experience with inorganics and cottonseed meal as well:

I have no problem to recommend inorganic fertilizers in small ponds where a moderate or light bloom already exists and where there are no existing macrophytic vegetation issues, but this is a rare occurence in Chad's area. Plus, the use of inorganic fertilizers only in this area have led to serious filamentous algae problems for some of my clients in the past.

I have had better luck in small ponds in Chad's area with small applications of cottonseed meal, like 100 lbs per acre with max of 2 apps per spring, in conjunction with a feeding program. The blooms tend to be more consistent, more predictable, more zooplankton heavy, and less maintenance. The use of inorganics assumes that phosphorous and nitrogen are limiting plankton nutrients. The use of organics will provide the basics but also carbon and many other nutrients that I am not qualified to list.

Note that we do have programs using inorganics only, but only on larger bodies of water.

In my mind the goal here is to predictably grow plankton without high risk of depleting oxygen. A good plankton bloom can represent significant "organic" biomass in itself, with a potential to both produce and consume oxygen, and with a potential to deplete oxygen as well.

Specific uses of specific quantities of organics like cottonseed meal at the right time of the year is no more "risky" than some of the other practices and programs we use to manage ponds and take for granted.

Fish food supplement is a source of organic nutrients as well and hasn't been addressed in this thread. How many of us have quantified the amount of accumulated fish waste affecting their ponds every year, indirectly, through supplemental fish food?

Use of herbicides to treat vegetation produce significant organic wastes that can be fuel for plankton, and most pros will agree that April/May are the best times for vegetation control programs in this area. How many of us have quantified the amount of organic biomass that is exposed to an aquatic system after a vegetation treatment?

I reserve the right to change my recommendations once we've seen Chad's pond, but for now I want him to be prepared to follow this plan. I also would like for him to document his progress and/or failures.