Friday, June 17, 2011

Ammonia: The Most Common Killer

     When fish finish digesting their food, they excrete a waste product known as ammonia through mostly their gill tissue and their kidney. Fish excrete waste through their gills by osmosis. Ammonia may collect in ponds when there is a presence of excess food, organic debris, and decay of dead fish tissues. When ammonia accumulates, it causes the fish’s skin to redden. It also damages the gills through its direct contact with them. If a fish’s gills are damaged to begin with, the fish cannot excrete ammonia normally. Furthermore, if the ammonia level in a pond is high, healthy fish cannot even excrete ammonia through their gills against this harsh gradient. In harsh conditions like so, fish will die.

     Fortunately, it is not hard to recognize the signs of fish suffering from ammonia poisoning. Fish will typically isolate themselves, clamp their fins, secrete excess slime, and lie on the bottom of the pond. Subsequently, ammonia depresses the immune system of fish by lowering the cortisol stress-response on important immune fighter cells. Ammonia has been known to do this at very low levels (0.25 ppm and below). When this occurs, fish have an increased risk of developing parasitic and bacterial infections. It is safe to say that no ammonia level should be considered tolerable in a pond. If you suspect your fish are suffering from ammonia poisoning, it is imperative that you purchase a water test kit as soon as possible. Drop type test kits include ammonia testing and are accurate and fairly inexpensive.

     If you have ammonia accumulations in your pond, the reason is probably due to overproduction of waste. Overproduction is either due to the number of fish in your pond or amount of feed. Another reason for ammonia collection is under-utilization, also known as an inadequate filter biomass or circulation. In new ponds, ammonia can be a significant issue because the bacteria that naturally reduce or remove ammonia are not established yet. In fact, ammonia can be a problem to all ponds. Ammonia may gather in the springtime when the water is cold but warm enough for fish to feed because bacteria have not usefully emerged from “hibernation”. In the fall, ammonia levels may appear as water temperatures decline and beneficial ammonia-reducing bacteria function less efficiently.

     From below a pH of 7.4, ammonia ionizes to the ammonium state, which deems it as less toxic to fish. When the pH is higher than 8.0, most ammonia is de-ionized, thus becoming increasingly toxic. You should not let the pH of your pond rise above 7.2 if there is a lot of ammonia present. It is a common misconception that you need to lower the pH or restrict aeration to fish to keep the pH down, which is thought to allow carbonic acid accumulation to hold down the pH to preserve ammonia in its non-toxic state. Considering this, never decrease aeration in show tanks just to hold down the pH for ammonia.

     Although ammonia can be a significant problem, there are many ways to lower its levels. Water changes, management of the pH near or just about neutral (7.2 to 7.4), and abbreviated feeding schedules will make a noteworthy difference. Some ammonia treatments include the use of various water conditions that bind ammonia and the application of rechargeable Zeolites (clinoptilolite ion exchanging resin) to the system filter. Water changes can be effective, if you follow certain guidelines. You may already know that water quality deterioration calls for a continual daily water change of 20-40% of the total volume in a pond. Keeping this mind, you should make sure the water change does not drastically differ the water temperature. It is important to check your water after a water change for a certain result-electrolyte poor water. On a side note, testing the total alkalinity of the water will detect this, as well as other salts.

     Adding a teaspoon of salt per gallon of water in a water change (where live plants are not present) can make a substantial difference in dealing with ammonia. By doing so, you will ease the stress from the water change on the fish and stimulate the production of a healthy, productive slime coating. The salt dose will not harm fish lacking scales. The best salt to use is table salt or sea salt. Iodized salt, also being harmless to fish, may be used, but there is popular belief that the Iodine can stun the beneficial bacteria residing in your filter. When doing daily, massive water changes, make sure the pH is not fluctuating significantly with each change. When treating the water, suspend or reduce feeding. Moreover, you should switch to Cheerios or another non-protein cereal. If you have a well, the pH of the water from it is either extremely low or extremely high, depending on where you live. Well water is known to come from a source with a very low oxygen level, or high levels of undesirable gasses and dissolved compounds.

     Zeolites, exhaustible clay resin that binds to ammonia from water, is another known ammonia treatment. This treatment works by measuring the ammonia in a pond at first, then recharging the Zeolites after. Once the ammonia returns after employing the Zeolites, it is time to recharge again. Even in stable systems, they should be used for no more than three to four weeks without recharging. Moreover, they can be recharged in a stiff saltwater solution (2-3%). If you are using salt for another purpose in your pond, you must remove the Zeolites. When exposed to salt, Zeolites dump their accumulated ammonia back into circulation. To actually recharge the Zeolites, fill a five-gallon bucket and put forty to fifty tablespoons of salt in it. After this, soak the Zeolites overnight and re-use the saltwater over and over for this. Zeolites will not starve your filter.

     If you are considering using a water conditioner to solve your ammonia problem, be cautious in your decision. For instance, there is a synthetic agent that coats fish with a protective coating that may be harmful to the fish. Until it is reformulated, it is likely that it may make a fish sicker than it already is. The compound, for example, will coat the fish’s gills if it already has serious parasitic or chemical gill damage. This can complicate respiration, since the gills were not functioning to begin with. Some conditioners are sold to bind ammonia. A few of these use aldehydes to solve this issue: however, aldeyhdes can accumulate and become caustic to fish if no ammonias are actually present. Although they are useful, they should be used only sparingly and judiciously.

Sources: "Ammonia in Fish Ponds Is Deadly to Fish. Pond Filters Remove It." Water Gardens, Fish Ponds: Build & Care for a Garden FishPond. Web. 03 Mar. 2011. . Johnson, Erik L. "Ammonia: Most Common Killer of New Fish." Koi Vet. Web. 3 Mar. 2011. . Johnson, Erik L. "Koi, Goldfish & Pond Health Ammonia & Koi Health - Ammonia or Ammonium - Measuring This Silent Killer." Koi, Goldfish & Pond Health In Twenty Steps. Web. 03 Mar. 2011.

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1 comment:

  1. Thank you for sharing information about ammonia removal. Municipal wastewater treatment poses two key challenges: nitrogen pollution and waste sludge disposal.