How many samples should be collected?
- Two separate
water samples may be required to address water related problems due to plumbing
and/or fixtures.
- One sample should be collected at the point of entry (well or water service) and another at the point of use (tank, pond, etc.). This sampling method will help to pinpoint to where plumbing repair is needed.
How much water should be included in the sample?
- In ponds larger
than 4000 m2, a minimum of two 500 ml water samples should be collected from
opposite ends of the pond for analysis.
What to test?
- If fish are
stressed or dying, immediately test the water for dissolved oxygen, carbon
dioxide, conductivity, pH, temperature, ammonia nitrogen, nitrite, alkalinity
and hardness.
- Additional water quality parameters to be analyzed include color, biological oxygen demand (BOD), calcium, iron, manganese, nitrate nitrogen, total suspended solids, turbidity, sulfate, chloride and phosphate.
- Organic contaminants
- Inorganics, such as heavy metals
When to do the water sampling?
- The timing for sampling water is critical for some variables.
- Water temperature, dissolved oxygen, and pH are lowest in the early morning and highest in the afternoon.
- Carbon dioxide concentrations follow the opposite trend.
- Although total ammonia nitrogen concentration does not exhibit a daily trend, non-ionized ammonia concentration does. The percentage of total ammonia in the unionized form is highest in the afternoon because of the higher water temperature and pH.
- Most other variables do not exhibit well-defined daily variations.
What information should be included with the samples?
- With each fish
sample sent to the diagnostic or toxicology laboratory the following
information needs to be submitted:
- Name, address and phone number of the submitter.
- Date of collection.
- Designation of pond or tank from which fish were collected..
- Dimensions of pond or tank, including depth.
- Species, number and average size of fish.
- Date of last fish stocking, including number, species and size.
- Amount of food fed per day. Indicate if fish are still eating or stopped eating.
- Date first morbidity or mortality observed.
- Approximate number of dead fish per day since mortalities first observed.
- Identify most recent chemical treatment, including date and amount.
- Determine clarity of water by Secchi disk depth.
- Provide water quality data of ponds or tanks.
Label water samples for the toxic substances laboratory
with the following information:
- Name, address
and telephone number of submitter.
- Date of collection.
- Designation of pond or tank from which water was collected.
- Method of preservation (ice, acid, etc.).