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Water Issues FAQ's

What is ammonia

Fish continually release ammonia (NH3) directly into the aquarium through their gills, urine, and solid waste. Uneaten food and other decaying organic matter also add ammonia to the water. High levels of ammonia quickly lead to fish death. Even trace amounts stress fish, suppressing their immune system and thereby increasing the likelihood of disease outbreaks and subsequent fish loss. Ammonia is easily measured with an ammonia test kit.


What causes an ammonia problem

A natural mechanism exists that controls ammonia in the aquarium - the biological filter. It is made up of nitrifying bacteria, which live in the gravel bed. However, as with any natural process, imbalances can occur. A newly set-up aquarium will not immediately have the right balance of bacteria and ammonia will build up. Over feeding and keeping too many fish in the aquarium will also cause an ammonia problem. Testing for the presence of toxic ammonia is essential, so that once detected, steps can be taken to remove it.


How do I prevent ammonia?

In a new freshwater pond/aquarium, the ammonia level may surge to 6 ppm (mg/L) or more, and then fall rapidly as the biological filter becomes established. The ammonia will be converted to nitrite (also toxic), then to nitrate. This process may take several weeks. In an established aquarium, the ammonia level should always remain at 0 ppm (mg/L). The presence of ammonia indicates possible over-feeding, too many fish, or inadequate biological filtration.


I have an ammonia problem - what now?

Overfeeding is a common cause of ammonia build-up. Make sure that all food is eaten within a few minutes. Sinking pellets and wafers should be completely eaten in 30 minutes. Uneaten food decomposes, adding ammonia to the water. To detoxify ammonia, use API’s AMMO-LOCK to instantly lock up ammonia. AMMO-LOCK does not remove ammonia, it simply converts toxic ammonia to a non-toxic form. Ammonia test kits will still test positive for ammonia, even though it is non-toxic. The biological filter will then consume the non-toxic ammonia, converting it to nitrite (Nitrite is another toxic waste material which must be tested separately) and then to nitrate. If the gravel bed is dirty from accumulated waste and uneaten food, use a gravel siphon to remove the debris. Changing 25% of the aquarium water will reduce the ammonia level. In an emergency, a daily water change may be required over several days.


What is nitrite

Nitrite (NO2-) is produced in the aquarium by the biological filter. Beneficial bacteria in the biological filter convert toxic ammonia into nitrite (also toxic). The biological filter then converts nitrite into nitrate (NO3-). Testing for the presence of toxic nitrite is essential, so that once detected, steps can be taken to remove it. Otherwise, nitrite in the aquarium will prevent fish from carrying on normal respiration. High levels of nitrite quickly lead to fish death. Even trace amounts of nitrite stress fish, suppressing their immune system and, thereby, increase the likelihood of disease and subsequent fish loss.


What is nitrite?

In a new freshwater pond/aquarium, the nitrite level may surge to 10 ppm (mg/L) or more, and then fall rapidly as the biological filter becomes established. The nitrite will be converted to nitrate. This process may take several weeks. In an established aquarium, the nitrite level should always remain at 0 ppm (mg/L). The presence of nitrite indicates possible over-feeding, too many fish, or inadequate biological filtration


What is "Water Hardness"?

General Hardness or GH is the measure of calcium (Ca++) and magnesium ions (Mg++) dissolved in water. General Hardness is measured with the GH Test Kit. Carbonate Hardness, also known as KH, refers to the concentration of bicarbonate (HCO3-) and carbonate (CO3--) dissolved in water. Carbonate Hardness is measured with the KH Test Kit.

Calcium and magnesium carry a positive charge and form "ion pairs" with negatively charged ions like bicarbonate, forming calcium bicarbonate and magnesium bicarbonate; Ca(HCO3)2 & Mg(HCO3)2.

Marine reef aquarists interested in measuring the calcium level in their aquariums should use a calcium test kit made specifically for this purpose. The KH Test Kit can be used to test the carbonate hardness in saltwater aquariums.


How do I test for water hardness?

GH and KH are easily measured with the GH & KH Test Kit. This kit measures GH and KH in German degrees (° dGH & ° dKH) and parts per million (ppm). Some aquarium literature refers to water hardness in degrees while others use ppm. Your aquarium water may have a high GH and KH, low GH and KH, or a situation where one type of hardness is high and the other low, i.e. low GH & high KH. If, for example, you have a water softener on your tap water supply the GH will be zero (or very low) while the KH, which is not removed by a water softener, will remain high.

In marine aquariums the KH is supplied by the synthetic seawater mix used to make saltwater. The KH level will depend on the particular brand of salt.


What effect does water hardness have on the pond/aquarium?

Water with a GH will contain a lot of calcium and/or magnesium. This is great if you are keeping African cichlids or other fish that like hard water. While excessive GH is not dangerous to tropical fish, many species come from water with a GH level of 35-ppm to 90-ppm (2-5° dGH). Most aquatic plants also prefer a GH level of 35-ppm to 90-ppm (2-5° dGH). Excess GH also contributes to white scale build-up on the aquarium lid and light fixture. As aquarium water evaporates calcium and magnesium (and other minerals) are left in the water causing GH to rise over time. Lowering GH (softening) has no effect on pH. Reducing the GH level does increase the effectiveness of Proper pH buffers (freshwater).

KH is important in relation to pH. KH, also known as alkalinity or buffering capacity helps stabilize the pH in the aquarium. Carbonate and bicarbonate ions give water its ability to resist increases or decreases in pH. Water with very low KH may experience wide fluctuations in pH because the buffering capacity is low. A high KH level indicates that the pH will be very stable. High KH is almost always associated with a high pH. This is not the case, however, when Proper pH buffers are added to freshwater aquariums. Proper pH products are true buffers. They will raise or lower pH to reach the pre-set pH level. Proper pH 7.0, for example, increases buffering capacity (KH) at pH 7.0. This means the buffering capacity is strong specifically at pH 7.0. The pH is "locked in" at 7.0.

KH can be adjusted in marine aquariums with Proper pH 8.2. Proper pH 8.2 increases KH by adding a blend of carbonate and bicarbonate buffers to the water. This adjusts the pH to a level of 8.2 to 8.4 depending on the existing buffer provided by the synthetic salt formula. Many marine aquarists try to maintain a KH level around 140 to 178-ppm (8 to 10 ° dKH).


Does evaporation increase water hardness?

Yes. When water evaporates, it leaves all the hardness minerals in the aquarium. When you add tap water back to the aquarium, it adds more hardness minerals, which remain as the water evaporates. Partial water changes help keep the water hardness from building up from evaporation. The best way to manage water hardness levels is the Tap Water Filter.


How do I reduce water hardness?

Reducing GH can be accomplished with the Water Softener Pillow. The Water Softener Pillow only removes GH and has no effect on KH. The easiest way to reduce GH and KH is with the Tap Water Filter. The Tap Water Filter will make de-ionized water with no GH or KH. You can than adjust the GH and KH with Electro-Right and pH Adjuster or use the de-ionized water to make water changes in your aquarium. Water changes with the Tap Water Filter will gradually reduce GH and KH through dilution. Adding de-ionized water to replace evaporated water prevents water hardness build-up.


What is phosphate?

Phosphorous is an essential element for plants and animals. Phosphorus, measured as phosphate (PO43-), enters the aquarium from fish and invertebrate waste and decaying organic matter, such as dead algae and uneaten fish food. Water treatment facilities may add phosphate to tap water to prevent pipe corrosion and reduce concentrations of heavy metals in drinking water.


Why test for phosphate?

While phosphate is required by fish and plants, too much phosphate can lead to cloudy water conditions. In saltwater aquariums, phosphate precipitates dissolved calcium (Ca2+) and magnesium (Mg2+) ions, inhibiting the growth of hard corals and other reef-building organisms


What level of phosphate is safe?

While phosphate is not harmful to fish, the phosphate level should be zero in saltwater aquariums and freshwater pond/aquariums, including those containing live plants. The phosphate level in a new aquarium will depend on the purity of the water used to fill the aquarium. Phosphate level in tap water can vary daily depending on the treatment process used. Phosphate tends to accumulate in established aquariums.


I have a high phosphate level. What should I do?

In a freshwater or saltwater aquarium use API’s Phos-ZorbT. Phos-Zorb is a filtration material that removes phosphate. Making partial water changes can also help reduce the nitrate level, especially if the initial phosphate level is very high. However, because many tap water supplies contain phosphate, it can be difficult to lower phosphate levels by this method. API’s Tap Water Filter will remove pollutants, including phosphate, from tap water, making water changes effective.