Pond Boss Forums GENERAL QUESTIONS Water chemistry Nitrogen test

Looking to have my water sample tested for Nitrogen and Phosphorous.

I have multiple options on my form from the lab.

Total Phosphorous is simple enough, but for the Nitrogen I have:

NO2 and NO3 as Nitrogen

Total Kjeldahl-N

Ammonia-N

Total Nitrogen

Which would I be looking for?

If you are planning to test the water from the 6400 acre lake, what do you hope to accomplish by testing the various parameters? IMO the acreage is too large to chemically amend or change the current water chemistry if some values are not optimum. What ever the results you will have to 'live' with the results good or bad. Not much water chemistry management is possible on a lake that size. Watershed management would be about the only adjustments that could be made if the lake is considered too eutrophic - productive that result in nuisance algae blooms.

My nutrient test is part of my ongoing 7 acre project and unrelated to the reservoir in my other post.

The 6800 acre lake is in the process of receiving 2) $25,000 grants that our association (championed by myself and others) applied for but again unrelated.

Well I think the Tech at the lab answered my questions.

Total P and NO2+NO3 as Nitrogen.

Method for testing P is EPA/600/R-93-100 365.1

Total phos is more for estimating how productive or eutrophic the system is and Ortho-P (aka soluable P) is more for determining what it is capable of growing i.e. algal potential.

OK I managed to catch it and add it.

I should note that "technically" the ortho P has a 48hr hold time when testing to lab standards for permitting etc. Also Total P and N require that the sample be stabilized with sulfuric acid.

My sample met neither of those, but for the level of accuracy that we are after here should be just fine.

Due to the specialized nature of the testing they do they have several different bottle sizes and pre treatment specs. There's really no way to fill out the form to have a single quart bottle separated (via pour off) to do other tests, but calling in they understand and can do so.