| Understanding the effect of the system in marine | | | | of course to never lower or raise salt levels by |
| environments is the key to mastering fish | | | | more than 0.002 per day). This means that you |
| keeping. | | | | need to start preparing your tank a few days |
| One of the leased talked about issues in marine | | | | before you introduce a new fish so that the salt |
| aquarium keeping is the need to facilitate the | | | | level is right when you bring the fish home Once |
| functioning of a fish's osmoregulation system. The | | | | the fish appear to be doing well for a week you |
| osmoregulation system is responsible for | | | | can slowly return the salt level to 1.025 and any |
| maintaining a healthy balance of fluids and salts | | | | time the fish appear stressed again it is worth |
| within the fish itself. | | | | reducing it to 1.018 again. Many of the corals will |
| The higher the amount of salt in the water the | | | | not enjoy the lower salt level and may not open |
| harder the osmoregulation system has to work | | | | up as well during this, but this will not lead to any |
| to maintain correct levels of salt and other | | | | long term problems. |
| minerals within the fish, so the higher the osmotic | | | | Another reason to lower your salt level before |
| pressure. | | | | introducing new fish is that although the ocean is |
| The salt levels a fish can tolerate will depend on | | | | commonly at a salt level of 1.025, and a perfectly |
| the environment from which the fish has evolved. | | | | run reef aquarium should match this, most |
| Freshwater fish can only handle very low osmotic | | | | aquarium retailers and wholesalers run their |
| pressure compared to saltwater fish which are | | | | aquariums at a salt level of 1.018. This is to allow |
| used to withstanding a higher level. Some fish are | | | | lower osmotic pressure which in turn reduces the |
| able to tolerate huge changes in salt level and | | | | prevalence of diseases among their fish. Because |
| osmotic pressure allowing them to travel from | | | | of this most reef tank are actually kept at 1.023 |
| the salt water oceans, up the waters of | | | | and fish only tanks at 1.020. |
| freshwater rivers. Fish that commonly live in both | | | | A different way to allow fish to gradually adapt to |
| fresh and salt water are known as brackish water | | | | higher salt levels is to use a quarantine tank which |
| fish. | | | | can house the fish for 2-4 weeks before it is |
| There are also many salt water fish that will | | | | introduced in the main display tank. This means |
| venture into fresh water at specific points in their | | | | that the main tank can remain at the desired salt |
| lives. Many marine fish such as Salmon will travel | | | | level while also allowing the fish to settle in and |
| right up fast following freshwater rivers to breed | | | | de-stress before it is introduced into the display |
| allowing their young to grow up in safer stream | | | | tank. Another advantage of using a quarantine |
| nurseries away from the threats lurking in the | | | | tank is that it reduces the levels of pathogen in |
| oceans. Once the offspring are large enough they | | | | your display tank. When fish are stressed, for |
| will return to the sea where there is adequate | | | | example when they are being brought home from |
| food for them to grow and thrive. | | | | an aquarium retailer, they release peaks levels of |
| A fresh water fish generally maintains its internal | | | | pathogens into the water. These pathogens are |
| salt level higher than that of the surrounding | | | | not only dangerous to the new fish, but can also |
| water. Its gills take in salt from the environment | | | | make your existing fish sick. If you have a |
| along with oxygen. A large amount of water is | | | | quarantine tank, you can medicate the fish |
| constantly diffused into a fresh water fish and | | | | separately and reduce the threat of disease in |
| excreted as urine so that its system is constantly | | | | your new and old fish. |
| being flushed. On the other hand, a marine fish | | | | Once the new fish is ready to be introduced into |
| has an internal salt level lower than the | | | | the main tank, you should slowly adjust the salt |
| surrounding water so the osmotic pressure | | | | and pH levels and also the temperature to that of |
| naturally pulls water out of the fish and pushes | | | | the display tank. This way, you don't have to |
| salt in. Consequently, to maintain the correct salt | | | | acclimatize the fish in your display tank but rather |
| level, a salt water fish needs to actively excrete | | | | easily transfer it across in a net. This quick and |
| salt out of its gills. | | | | simple move from the quarantine tank to the |
| A marine fish in water with a slightly higher salt | | | | display tank will be stress free compared to what |
| level will devote more molecular energy to | | | | the fish has had to go through to get to you. |
| osmoregulation; therefore if the fish is suffering | | | | Given all the advantages, it is very advisable to |
| from stress lowering the salt level will help the fish | | | | use a quarantine tank. However, if the quarantine |
| to recover. Lowering the salt level will reduce | | | | tank is too small or you cannot provide the |
| osmotic pressure within the fish allowing it to | | | | correct conditions, then the fish are better off |
| allocate more of its molecular energy to its | | | | being introduced straight into the main tank. |
| immune system, This will help stop the stressed | | | | All the techniques mentioned above can be used |
| fish from becoming sick and can be used to treat | | | | whenever any of your fish are sick or stressed, |
| fish that are sick. | | | | not only at the time they are introduced. You can |
| The ocean is the most stable ecosystem in the | | | | at any time place a stressed or a sick fish in a |
| world occupying 77% of the earth's surface area | | | | quarantine tank with a lower salt level compared |
| and experiences very little seasonal fluctuations in | | | | with that of your display. Another approach is to |
| salt levels in comparison to tiny freshwater lakes | | | | perform a freshwater dip on any sick fish or |
| and rivers. Most marine fish can only handle about | | | | coral. To do this, place the sick marine animal in |
| 2 degrees of salt change per day e.g. 1.023 to | | | | freshwater with the same temperature and pH as |
| 1.025. Understating the osmoregulation system | | | | your tank for 10 minutes. This allows the osmotic |
| can help protect your display aquarium. Every fish | | | | pressure to kill any pathogens and bacteria that |
| you introduce will be initially stressed and it will | | | | maybe affecting your animal but usually not killing |
| usually take about 3 weeks for the fish to settle | | | | it. In most cases, if the animal does not survive |
| in to a new environment and for its stress levels | | | | the freshwater dip it was probably not strong |
| to return to healthy levels. During this time it's | | | | enough to survive anyway. The dip can be |
| advisable to lower the salt level of your water to | | | | repeated daily if necessary. |
| about 1.018, to decrease the osmotic pressure | | | | So next time your fish are experiencing stress or |
| experienced by the fish and then gradually | | | | illness, help boost their immune system by |
| increasing it to your previous level (remembering | | | | relieving osmotic pressure. |