Cooperative / Extension Program University of Arkansas at Pine Bluff Understanding Your Water Analysis Report Nathan M. Stone Figure 1 Extension Fisheries Water Analysis Report: Fish Specialist (Example)

Hugh K. Thomforde pH ------7.24 Extension Aquaculture Some sportfish and aquaculture Electrical Conductivity - - -205 mSiemens/cm Specialist pond owners choose to submit water Alkalinity, Total - - - - - 100.00 mg/l as CaCO3 samples to the University of Hardness, Total - - - - -103.80 mg/l as CaCO3 Arkansas Cooperative Extension CO (Carbonate) - - - - - 0.09 mg/l as CaCO Service for analysis. The water 3 3 samples are mailed to the Water HCO3 (Bicarbonate) - - 99.90 mg/l as CaCO3 Quality Laboratory, Arkansas Water Fe (Iron) ------0.05 mg/l Resources Center, University of Mn (Manganese) ------0.01 mg/l Arkansas at Fayetteville. The labora­ F (Fluoride) ------0.15 mg/l tory tests the water and sends the Cl (Chloride) ------3.13 mg/l results back. Below are some guide­ lines for interpreting those results. SO4 (Sulfate) ------3.21 mg/l These guidelines describe how to NO3 (Nitrate) ------0.04 mg/l

interpret results for both surface NO3-N (Nitrate-Nitrogen) ------0.01 mg/l waters and ground waters. Surface NH -N (Ammonia-Nitrogen) - - - - - 0.11 mg/l waters are those exposed to the air 3 and sunlight, such as streams, , NO2-N (Nitrite-Nitrogen) ------0.00 mg/l and lakes. Ground waters PO4 (Phosphate) ------0.06 mg/l are waters from wells or springs tapping underground aquifers and are often devoid of dissolved oxygen. These waters may also contain high Interpretinglevels of dissolved Results gasses or iron. It is important to know the source of the water sample (surface water or ground water) in order to interpret the results correctly. to 14 with 7 being neutral. In fish ponds, the time of day that a sample is taken often will influence the pH because of variations2 in the carbon Figure 1 is an example of a pond dioxide (CO ) concentration. As plants water analysis. An explanation of each in the water remove carbon dioxide for parameter listed inpH the report follows. photosynthesis, the pH will increase. While most of these parameters are At night, the pH will decrease as impoDesirablertant in Range fish culture Acceptable, others Rangeare carbon dioxide accumulates. measured6.5-9.5 incid entally in the5.5-10.0 proce ss of Increasing the total alkalinity concen­ water analysis and are ordinarily of tration in water helps buffer against little concern. pH changes. Most fish species do well within the pH range of 6.5 to 9.5. Chronic pH levels below 6.5 may reduce fish reproduction and are asso­ University of Arkansas at Pine Bluff, United States Department of Agriculture, and Countyciated Governments with fish Cooperating die-offs that some­ times occur in the late winter. Newly The pH of water is a measure of hatched fish (fry) are often sensitive how acid or basic it is, on a scale of 0 to pH levels above 9.0 t o 9 . 5 . Hardness, Total

Desirable Range Acceptable Range

50-150 mg/l as CaCO3 Above 10 mg/l as CaCO3

The pH of water sent to the testing laboratory will change during shipment, especially for wa t e r s that have significant amounts of organic matter ( e. g. , algae and bacteria) or elevated carbon dioxide c o n c e n t r a t i o n s. N e v e r t h e l e s s, pH testing is useful to detect possible mineral acidity. A pH reading below 4.5 indicates thatElectrical there is Conductivity strong mineral acidity, Total hardness is a measure of the calcium and w h i ch is harmful to fish and difficult (expensive) magnesium concentrations in wa t e r. Other divalent t o n e uDesirable t r a l i z e. Low Range pH between 4.5Acceptable and 6.5 Rangecan oft en ions (those with 2+ charges) contribute to total hard­ ness but are usually present in insignificant be corrected100-2,000 mbySiemens/cm the addition of30-5,000 crushed m Siemens/cmlimestone (see SRAC Fact Sheet No. 4 6 4 ) . a m o u n t s. The amount of calcium hardness is impor­ tant in pond fertilization because higher rates of CO (Carbonate) and HCO (Bicarbonate) phosphorus3 fertilizer are required3 at higher calcium hardness concentrations. At least 5 mg/l of calcium hardness is needed in water supplies. m Like total alkalinity, total hardness will not ch a n g e very much during shipment.

Electrical conductivity (EC) is a measure of how well a solution conducts electricity and is correlated Carbonate and bicarbonate, together with with salt content. Conductivity is typically reported in dissolved carbon dioxide, are components of total units of Siemens/cm (microsiemens per centimeter). m alkalinity (see “Alkalinity” above). The relative generally thrive over a wide range of amount of each of these compounds depends upon the electrical conductivity. Some minimum salt content is pH of the water sample. As such, there are no specific Fe (Iron) and Mn (Manganese) desirable to help fish maintain their osmotic balance. recommendations for levels of these compounds. The upper range varies with fish species. Channel Instead, see “Total Alkalinity” and “pH.” SRAC Fact m catfish, for example, can withstand salinities up to Sheet DesirableNo. 464 (seeRange “Sources of Information”)Acceptable Range provides 1/2-strength seawater. Seawater has a conductivity of additionalFor hatchery information water: on theFor relationship hatchery water: among around 50,000 to 60,000 Siemens/cm. Electrical Alkalinity, Total theseFerrous parameters iron: none. No ferrous iron conductivity (EC) also can be used to give a rough Ferric iron: none Ferric iron: Less than estimate of the total amount of dissolved solids (TDS) 0.1 mg/l for fry, less than in waterDesirable. Typically Range, the TDS valueAcceptable in mg/l isRange about 1.0 mg/l for most fish half of the EC ( Siemens/cm). Conductivity should 50-150 mg/l as CaCO3 Above 20 mg/l and less than For pond water: Any level of For pond water: Any level of change little during shipment to400 the mg/l laboratory for ponds. ferric iron, no ferrous iron. ferric iron, presence of Above 10 mg/l for hatchery ferrous iron acceptable if water (measured as CaCO3) limited to zone around water inlet (see text). Manganese: 0-0.01 mg/l Manganese: Up to 1 mg/l

Total alkalinity (TA) is a measure of the Farm Pconcentrationond Management of bases for Recreational(typically carbonate and bicarbonate) in the water that provide buffering These two elements behave similarly and will be capacity. The units are milligrams per liter (mg/l) as discussed together. Well water may contain elevated calcium carbonate. TA below 20 mg/l limits primary levels of iron (ferrous iron) and manganese but still in water, and ponds with such water appear clear to the eye. When the well water is benefit from lime. See our publication MP360, exposed to oxygen, the iron is changed into rust , for (ferric iron), giving the water a rusty brown color. information on liming ponds. Application rates of Water high in iron and/or manganese should be copper sulfate for algae control are based on the TA of treated before use in a fish hatchery. Typically, well the water, and copper sulfate should not be used at all water is aerated to oxidize the iron and manganese, in waters with fish if the TA is less than 50 mg/l. and then the water is passed through a sand filter to remove the floc (small clumps). Ordinarily, waters The total alkalinity of a surface water sample high in these elements can be used “as is” for outdoor sent to the testing laboratory usually will not change culture ponds. If a pond must be stocked immediately significantly over the 2- to 3-day shipping period. after filling, aeration can be supplied to speed the NH3-N (Ammonia-Nitrogen)

Desirable Range Acceptable Range

Total NH3-N: 0-2 mg/l Total NH3-N: Less than 4 mg/l F (Fluoride) Un-ionized NH3-N: 0 mg/l Un-ionized NH3-N: Less than oxidation process and render the water safe for fish. 0.4 mg/l While the relative amounts of the forms of iron or manganese might change during shipment, the total values will be unaffected.

Fluoride is a traceCl e(Chloride)lement typical ly present in water at levels of 0.1 to 1.5 mg/l. It may be added to water as a measure to prevent tooth decay in humans Ammonia is a dissolved gas present naturally in (0.7Desirable to 1.2 mg/ Rangel). Le vels at or abAcceptableove 3 mg/ lRange are re ported surface and wastewaters, and in some well waters. It is the major nitrogenous waste product of fish and to causeAbove lo sse60 smg/l of some fish10 timesspecies, the depenitritendi concentrationng upon comp(forle catfishx water ponds) condi tions. (for catfish ponds) also results from the decomposition of organic matter. It is quite soluble in water, especially at low pH, and ordinarily is removed by plants or bacteria (as a 3 nutrient or energy source).+ Ammonia in water is 4 Chlorine present in two forms – un-ionized ammonia (NH ) and the ionized form (NH ) – and the relative proportion of each type depends on pH and tempera­ Chloride - ture. As pH increases, there is an increasing propor­ tion of un-ionized ammonia, which is very toxic to Chloride (Cl ) together with sodium (Na) forms fish. In addition to pH, the toxicity of ammonia to fish common salt (sodium chloride). Chloride2 should not varies with the fish species and whether the fish has be confused with the gas, chlorine (Cl ). is a time to adjust to elevated levels. Catfish acclimate to highly reactive compound and is used as a disinfec­ high ammonia levels, and in commercial ponds, 2 to tant. is the same element in the form of a 5 mg/l of total ammonia nitrogen is common in the and fall. For more information on ammonia in salt. Chlorine and chloride have dramatically NO (Nitrite) and NO -N (Nitrite-Nitrogen) different chemical properties. Chloride is a common fish ponds2 , see SRAC Fact Sheet2 No. 463. Ammonia component of most waters and is beneficial to fish in values in surface water samples shipped to the labo­ maintaining their osmotic balance. In commercial ratoryDesirable are not Rangereliable , as levelsAcceptable often will Rangeincrease catfish production, chloride (in the form of salt) is during shipment due to bacterial decomposition of 0-1 mg/l NO Less than 4 mg/l NO often added to waters to obtain a minimum concen­ organic matter, especially2 during the warmer months2 . tration of 60 mg/l. This is done because catfish are SO (Sulfate) susceptible to “brown blood”4 disease, caused by excess nitrite in the water. A ratio of chloride to nitrite of 10:1 reduces nitrite poisoning. High chloride levels (above 100 mg/l) are a concern only if the water is also used to irrigate sensitive land-based crops.

Nitrite is another form of nitrogenous waste Sulfate is a common compound found in water as product that can be found in pond water. Typical a result of the dissolution of minerals from soil and concentrations range from 0.005 to 0.5 mg/l. NO (Nitrate) and NO -N (Nitrate-Nitrogen) rocks. Typical3 levels are between3 0 and 1,000 mg/l. Ammonia can be transformed into nitrite, and nitrite Fish tolerate a wide range of sulfate concentrations, to nitrate, by certain bacteria. In commercial catfish and levels of sulfate above 500 mg/l are a concern ponds during the spring or fall, nitrite levels can only if the water is used for other purposes, such as increase greatly. Salt is added if necessary to prevent watering cattle. “brown blood” disease (see “Chlorides”). The toxicity of nitrite to fish varies greatly with the species of fish. Some species are quitePO (Phosphate)susceptible while others are very resistant. For more4 information on nitrite in fish Nitrate levels in drinking water for humans and ponds, see SRAC Fact Sheet No. 462. As with livestock are a major concern. Typical levels in ammonia, nitrite levels in surface water samples may surface waters range from 0.005 to 0.5 mg/l nitrate. change during shipment to the laboratory and are However, nitrate is relatively nontoxic to fish and is not reliable. not a health hazard3 except at exceedingly high levels (above 90 mg/l NO -N). Nitrate and nitrate-nitrogen are two ways of expressing the same parameter. Almost all of the phosphorus4 (P) in water is in Nitrate-nitrogen expresses the concentration of the form of phosphate (PO ) . M u ch of the phos­ nitrate based only on the weight of the nitrogen in phorus in surface water is bound to living or dead the nitrate (to convert nitrate-nitrogen concentrations particulate matter. Phosphorus is an essential plant to nitrate, multiply by 4.43). n u t r i e n t , and because it is often in limited supply, , ,

adding phosphorus to water will stimulate plant parameters do vary among fish species. If the water is (algae) growth. This growth of algae can be undesir­ also used for other purposes, s u ch as watering livestock a b l e as in the case of pristine streams, or desirable or crop irrigation, be sure to ch e ck recommended levels as in ponds for fish culture. The typical range for of the various compounds for these uses. In all cases, i t surface waters is 0.005 to 0.5 mg/l. G r o u n d wat er in Sourcesis important toof remember Information that the se tests cannot the Arkansas delta may contain significant concen­ detect all possible water quality problems. S u ch testing trations of phosphorus. In the Lonoke area, f o r would be prohibitively expensive. In Padonddition, Aquaculture wa t e r e x a m p l e, the average for wells in the alluvial aquifer supplWyater charact Qualityeristics Management can ch a n g e, so it is important to is 0.33 mg/l. Ponds on watersheds fertilized with re-test waters periodically. ch i cken litter or with livestock may be fertile (or excessively fertile) due to the influx of phosphorus Water for Beef Cattle from animal wa s t e s. Considerable care in sample cSummary o l l e c t i o n , handling and preservation is required to obtain truly accurate phosphorus values. R e s u l t s Boyd, C. E., and C. S. Tucker. 1998. from samples shipped through the mail to the . Kluwer Academic laboratory may differ significantly from the PublishersAmmonia, Norwell, in Fish Massachusetts Ponds . a c t u a l v a l u e s. Davis, G. V., Jr. 2000. , FSA3021, University of Arkansas Cooperative Extension Farm Pond Management for Recreational Fi s h i n g Service, Little Rock, Arkansas. Many of the water quality problems faced by pond Durborow, R. M., D. M. Crosby and M. W. Brunson. owners and fish farmers may not be resolved by the Nitrite in Fish Ponds 1997. , Fact Sheet results of the Water Quality Laboratory testing. Fo r No. 463, Southern Regional Aquaculture Center. e x a m p l e, a common pond problem and the leading cause of fish kills is low dissolved oxygen (see MP360, Available at: http://www.msstate.edu/dept/srac/ , f o r fslist.htm. additional information). Dissolved oxygen must be Farm Pond DurborowManagement, R. M., D.for M.Recreational Crosby and Fishing M. W. Brunson. measured on-site, as it changes dramatically during 1997. , Fact Sheet No. 462, shipment to the laboratory. S i m i l a r l y, well water prob­ Southern Regional Aquaculture Center. Available lems such as high carbon dioxide or hydrogen sulfide at: http://www.msstate.edu/dept/srac/fslist.htm. cannot be detected in samples shipped by mail. Wa t e r Water Quantity and Quality quality parameters such as pH and ammonia will be Goodwin,Requirements A., J. Jackson, for Channel N. Stone Catfish, T. Burnley Hatcheries, influenced and altered by organisms (e. g. , b a c t e r i a ) J. Farwick and M. Armstrong. 2004. naturally present in the pond water samples. R e s u l t s , MP360, from the water testing service are rarely helpful in Cooperative Extension Program, University of determining the cause of a . Arkansas at Pine Bluff, Pine Bluff, Arkansas. In the event of a fish kill, determination of the Interactions Tucker, C. S. 1991. cause of the problem may require specialized tests of pH, Carbon Dioxide, Alkalinity and Hardness , and rapid analysis. For help, contact your county in Fish Ponds agent or the nearest UAPB Fish Disease Diagnostic Fact Sheet No. 461, Southern Regional L a b o r a t o r y. If a pesticide is suspected, contact the Aquaculture Center. Available at: Arkansas State Plant Board for advice and informa­ http://www.msstate.edu/dept/srac/fslist.htm. tion regarding sample preservation and specialized Wurts, W. A., and R. M. Durborow. 1992. t e s t i n g. The Water Quality laboratory does not test for pesticides or other poisons. , Fact Sheet No. 464, Southern AccreditedMost Byw ateNorthrs Centralare suita Associationble for offish Colleges producti and on,Schools, CommissionRegional on Institutions Aquaculture of Higher Education, Center. 30Available N. LaSalle, at: Suite 2400, Chicago,although Illinois tolera 60602-2504,nces to differe 1-800-621-7440.nt wate r qualFAX: 312-263-7462ity http://www.msstate.edu/dept/srac/fslist.htm. DR. NATHAN M. STONE DR. HUGH K. THOMFORDE Printed by University of Arkansas Cooperative Extension Service Printing Services.

is Extension fisheries specialist and Issued in furtherance of Extension work, Act of September 29, 1 9 7 7 , i n is Extension aquaculture specialist. cooperation with the U. S. Department of A g r i c u l t u r e, D r. Jacquelyn W. Both are with the Cooperative Extension Program, University of M c C r ay, Dean/Director of 1890 Research and Extension, C o o p e r a t i v e Arkansas at Pine Bluff. Extension Program, University of Arkansas at Pine Bluff. T h e Arkansas Cooperative Extension Program offers its programs to all eligible persons regardless of race, c o l o r, national origin, r e l i g i o n , g e n d e r, a g e, d i s a b i l i t y, marital or veteran status, or any other legally FSA9090-PD-7-04N protected status, and is an Equal Opportunity Employer.