Which freshwater fish can live in saltwater

Gibbs--they can eat algae like crazy. I second the mollies and the guppys Both brakish. Find More Posts by funman1. Black belt cichlids, I would think they aren't reef safe though But I believe thet are truly brackish.

Let's see, mollies, platties, Orange chromide cichlids. Dont forget green spot puffers I have a boatload of mollies breeding live food in my sump and a figure 8 puffer in another tank. The reason for the mollies is obvious, I like having the figure 8 in salt because it is far better looking in salt water, I love puffers' personalities, this puffer doesn't require the space that most puffers do, and it was 7 instead of 40 dollars.

It's also just something different. Mollies can convert to full saltwater. They are commonly found up to 2 miles out in the Florida Keys. I'm not sure how long it will survive in full sw Green spotted puffers start out as freshwater, moving through brackish higher and higher until they are finally in full marine as adults.

Any fish that can live in brackish water can survive in marine conditions. Brackish water is that which has more salinity than freshwater but not as much as seawater. If usually results when freshwater and seawater mix, such in the case of estuaries or aquifers. The water appears quite dark in color with a salt concentration greater than 30 per cent. Fish that are commonly found in brackish water include catfish, gobies, puffers, monos, and scats.

These fish can live in both freshwater and saltwater aquariums. Guppies and mollies can also live in a brackish tank. Therefore, if you intend to convert your tank, be sure the fish you have can survive the changeover. Only a few species of freshwater fish can live in both brackish and freshwater conditions. Some species like bettas, for example, prefer brackish water but can also live in freshwater, provided it is extremely hard. Anadromous fish like salmon or trout are born in freshwater but spend most of their lives in saltwater that has a maximum salinity of 50 per cent compared to brackish water which is 30 per cent.

If you put most freshwater fish into saltwater, the water inside their bodies will expel due to the high saline concentration. This will cause the fish to die of dehydration in mere minutes. Only fish found in brackish water can be converted. Putting saltwater fish into a freshwater tank would ultimately have the same dire consequences.

The bodies of saltwater fish require a high level of salinity. You should upgrade or use an alternative browser. Freshwater fish in saltwater tank? Thread starter Sharkbait Start date Oct 13, Sharkbait Active Member.

I saw a Mollie in a huge saltwater tank, and it made me start thinking. I'm curious about acclimation of freshies to saltwater. I want to know what fish can be switched. I know mollies can, what else?

Does anyone know the procedure? Woodstock The Wand Geek was here. It seems like any brackish fish could be acclimated to full salinity BoomerD Well-Known Member. Mollies aren't actually freshwater fish, but rather brackish water. They can be acclimated quite nicely to saltwater, but of course, since this is not their natural habitat, they don't usually live as long.

Supposedly they are more nutritious than goldfish for the salt water predators. BoomerD said:. Click to expand Witfull Well-Known Member.

Where's all the saltwater frogs? It was the constant evaporation of water from the oceans that then condensed to cause rainfall on the land masses, which in turn, caused the oceans to become salty over several billion years. As rain water washed over and through the soil, it dissolved many minerals--sodium, potassium and calcium-- and carried them back to the oceans. Vertebrate animals fish, birds, mammals, amphibians and reptiles have a unique and common characteristic.

The salt content of their blood is virtually identical. Vertebrate blood has a salinity of approximately 9 grams per liter a 0. Almost 77 percent of the salts in blood are sodium and chloride. The remainder is made up primarily of bicarbonate, potassium and calcium. Sodium, potassium and calcium salts are critical for the normal function of heart, nerve and muscle tissue. If the salinity of ocean water is diluted to approximately one quarter of its normal concentration, it has almost the same salinity as fish blood and contains similar proportions of sodium, potassium, calcium and chloride.

The similarities between the salt content of vertebrate blood and dilute seawater suggest a strong evolutionary relationship among vertebrates and with the primordial oceans. Indeed, it seems likely that vertebrate life evolved when the oceans were approximately one quarter as salty as they are today. As the oceans became saltier and vertebrates evolved further, several groups of vertebrates birds, mammals, reptiles and amphibians left the oceans to inhabit the land masses, carrying the seawater with them as their blood.

They maintained their blood salt concentrations by drinking freshwater and absorbing salts from food. But fish stayed in the aquatic environment. To adapt, they had to either remain in low salinity environments, such as bays and estuaries, or they had to evolve mechanisms to replace water lost through osmosis to the seawater and to remove salts absorbed from the increasingly saline oceans. To inhabit freshwater, fish had to replace salts lost through diffusion to the water and eliminate excess water absorbed from the environment.

Kidney function had to be altered accordingly for fish to survive in these different habitats. In seawater, fish must drink salt water to replace lost fluids and then eliminate the excess salts. Their kidneys produce small volumes of fluid containing high concentrations of salt. Freshwater fish produce large volumes of dilute urine, which is low in salt.

Less demand is placed on the kidneys to maintain stable concentrations of blood salts in brackish or low salinity waters. Ultimately, fish adapted to or inhabited marine, fresh or brackish water because each environment offered some competitive advantage to the different species. For instance, it has been suggested that euryhaline fish are able to eliminate external parasites by moving to and from fresh and saltwaters.