Brackish-water aquarium :
A brackish-water aquarium is an aquarium where the water is brackish (semi-salty). The range of "saltiness" varies greatly, from near freshwater to near marine and is often referred to as specific gravity (SG) or salinity. Brackish water aquaria is a popular specialization within the fishkeeping hobby. Many species of fish traded as freshwater species are actually true brackish species, for example mollies,Florida flagfish, and some cichlids such as chromides and black-chin tilapia. There are also several popular species traded purely as brackish water fish, including monos spp, scats, archerfish, and various species of pufferfish, goby, flatfish, and gar. Generally, aquarists need to maintain a specific gravity of around 1.005 to 1.010 depending on the species being kept, but practically all brackish water fish tolerate variations in salinity well, and some aquarists maintain that regularly fluctuating the salinity in the aquarium actually keeps the fish healthy and free of parasites.
Video : The Brackish Fish Tank Experiment
A brackish water fish: Siamese tigerfish, Datnioides pulcher
Aquarium maintenance :
Brackish water species can be kept mainly the same as standard freshwater aquaria, but a hydrometer is used to check the salinity of the water. Certain kinds of brackish water fish need to have their salinity increased slightly every six months. The tank sizes can vary widely depending on the needs of the particular species, and the temperature is usually in the tropical range of 76-82 °F. The substrate can vary from sand to gravel, but many aquarists choose crushed coral or aragonite sand, both of which help raise the hardness and pH to an acceptable level. Many brackish water fish, as any fish, can jump out of the tank, so it must be covered. Some brackish water species come from estuaries. These should have a slow moving current and some hiding places in their aquarium. Some come from larger rivers. These should have plants around the perimeter of the aquarium with some large rocks to rest on. Others come from mangrove swamps. These should have a few mangrove plants, and some species should have a beach to climb out on. Some freshwater species (and the blacktip shark, a marine species) are hardy enough or survive better in brackish water, such as Polypterus bichir, certain loaches, Danio rerio, all kinds of mollies but especially the Yucatán molly, and some gobies. All can tolerate the same amount of salt in aquaria, but should be acclimated slowly.
External links:
-Aquariacentral Brackish Water Forum FAQ
-Brackish Water Fishes
-Estuarine Aquarium Keeping, Chesapeake Bay National Estuarine Research Reserve
Setting up and cycling a new brackish water aquarium
7 Brackish Water Aquarium Basics You Should Know
courtesy to : homeaquaria.com/brackish-water-aquarium-basics/
If you’ve ever purchased a Dragon Goby, Colombian Shark Catfish, or Fiddler Crab for your freshwater tank and found that they never thrived, it’s because these (and many other “freshwater” fish and invertebrates) are actually brackish!
A brackish set up can be very interesting in their own right and can be a good stepping stone towards starting Marine tanks.
1. What Are Brackish Tanks?
A “brackish” system is identified by water that has a specific gravity between that of freshwater (a specific gravity of 1.000) and full saltwater (around 1.021-1.025).
Specific Gravity is a measure of density of aquarium water relative to that of pure water and in brackish tanks is modified through the addition of Marine Salt Mix.
A hydrometer can be used to measure Specific Gravity and is available inexpensively at most pet stores. More accurate tools like refractometers are available and are often used for Marine Tanks for advanced hobbyists.
However, hydrometers are “good enough” for brackish tanks as these fish are less finicky about specific gravity than the often delicate corals and cnidarians kept in reef tanks.
2- Aquarium Salt vs. Marine Salt
Aquarium Salt : (Sodium Chloride – the same as kosher salt and cooking salt) is often sold for use as freshwater medication.
Although this raises the salinity of water, it does not provide the same benefits of increase General Hardness (dH), Carbonate Hardness (KH), or any of the other trace minerals that is found in brackish water.
Marine Salt mix : (a composition of Sodium Chloride, Magnesium Bicarbonate, Calcium Bicarbonate, and other elements) is needed for the long term health of brackish fish and invertebrates.
This mimics the water found in their natural habitats, where water from the ocean mixes with fresh water from rivers and streams.
3. Modifying Specific Gravity
Raising and lowering of Specific Gravity is accomplished through water changes. When you do your weekly maintenance, you add in water with a specific gravity that will bring your tank to where you want it to be. It may take a little math, but it’s not too difficult.
Many fish aren’t fussy about how quickly changes are performed, but for the benefit of all (including filter bacteria), it’s best not to jump more than .002 specific gravity at a time.
Let’s give an example: say you have a 40 gallon freshwater tank and want to convert to brackish without removing the fish. If you replace 10 gallons of fresh water (25% of the tank) with brackish water at 1.008 specific gravity, this will bring the tank to a whole up to 1.002.
The next week, you can bring to 1.004 by replacing 10 gallons of tank water with 10 gallons at about 1.010, and so on.
4. Cycling a Tank :
Tank Cycling is performed the exact same way as in Freshwater and Marine tanks; the addition of an ammonia source over a few weeks to establish the bacteria that convert Ammonia to Nitrites, and Nitrites to Nitrates.
The process is simplified more if you are converting a cycled freshwater tank to low end brackish (at/below 1.005) or have cycled filter media. Just take your desired tank and add enough Marine Salt mix to raise the Specific Gravity by .002 per week.
The freshwater bacteria can adjust to these conditions and within two or three weeks you will have the specific gravity where you’d like it and a cycled tank, all with fish still in the system!
For higher salinity tanks, you can either go the same route (if fish are in the system) or for tanks without livestock you can add the salt mix in to get to the desired specific gravity and cycle normally.
5. Adjusting Livestock
For current brackish-tolerant livestock, the same increase in Specific Gravity of .002 per week will suffice for almost all species of fish and inverts. Certain fish are less demanding than others here;
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the Target Fish (Terapon jarbua)
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and the Molly (Poecilia sphenops, P. latipinna, and P. velifera)
are all famous for being able to thrive in Marine tanks straight from Freshwater conditions, but even the Volitans Lionfish (Pterois volitans) is found in estuaries noted for having .020 changes every 6 hours.
For any new livestock purchased from freshwater (a common practice with “Freshwater” Morays and “Freshwater” Horseshoe Crabs, among others), they should be kept in a Quarantine tank and slowly acclimated to the main tank specific gravity.
If a fish purchased this way is having orientation or skin issues (owing from incorrect environment), adding additional Marine Salt to the tank should help correct this issue.
6. Marine Tools of the Trade
Although Brackish Tanks can be handled more or less like Freshwater tanks, at higher specific gravities you can utilize some of the Marine Tank standard practices.
Deep sand beds (also useful in Freshwater tanks but more associated with Marine Tanks) can finish the Nitrogen cycle by converting Nitrates to harmless Nitrogen gas (denitrification).
At or above 1.010, protein skimmers can be utilized, albeit not as effectively as they are in Marine Tanks. Protein Skimmers are useful for removing dissolved organics from water and are more effective than Carbon filtration at this task.
A properly sized protein skimmer (rated for turnover about equal to tank volume per hour) can be very effective at keeping Nitrates and Phosphates low.
Around 1.015, Live Rock is usable (though it’s technically usable under this Specific Gravity, this level of salinity will keep the bacteria on the rock working more effectively). Live rock is used to assist in denitrification and can also provide grazing material for tank livestock.
7. Decorating :
Perhaps surprisingly, many plants available for freshwater tanks will thrive in low end brackish conditions (up to 1.003). Plants from the common genera
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Anubias,
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Cabomba,
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Ceratophyllum (Hornwort),
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Elodea (Anacharis),
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Cryptocoryne,
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Hygrophila (Wisteria),
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and Vallisneri
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will do well in these conditions, and Java Ferns will tolerate up to 1.005.Read
There are few available plants which tolerate more than this (including Seagrasses and Mangroves) but these can be very high maintenance and plastic plants may be better choices for most applications.
There are several options for Brackish Tanks that can’t support plants. Rocks are more common than Driftwood in these environments usually (though the water should be sufficiently alkaline to prevent a drop in pH from tannins) and sticking with a few large rocks of the same type is more natural-looking than several smaller rocks of different origins.
Some rocks, such as Limestone, have the added benefit of raising the hardness of the water.
Shells can be useful; in addition to naturally being found in estuaries, they also keep the water hardness high and can provide places for smaller fish to hide. A common biotope is taking several oyster shells and using Cyanoacrylate (“crazy glue”, which is aquarium safe) to adhere them to driftwood or rocks to form oyster reefs.
The quality of aquarium ornaments has risen in recent years, too. In fact, fake Mangrove Roots are largely better than live Mangroves for all but the biggest tanks and most experienced aquarists. The fake roots even have better longevity than the driftwood shaped as such, as they do not dissolve over time and do not release tannins in the water.
Any substrate adequate for freshwater use is also an option for brackish tanks. Soft silica sand is best for low end conditions and burrowing fish (like the Spiny Eels of the family Mastacembelidae), though other options (such as Aragonite or Crushed Coral mixed in with sand) can be used with less delicate fish to keep the hardness of the water high.
Final Words On Brackish Tanks
The Brackish Aquarium is surprisingly easy to get started. Though there are some tricks depending on the set-up, for the intermediate aquarist with Freshwater or Marine Tank experience, there should be no significant problems moving to Brackish.
Introduction :
Where the ocean meets outward flowing rivers, saltwater and freshwater mix. These areas are called estuaries, mangrove swamps, and salt marshes. The water, which is part saline and part fresh, is referred to as brackish. These brackish waters are home to an amazingly diverse and unique group of animals, some of which are commonly available to keep in the home aquarium. These fish include archers, scats, monos, certain livebearers, gobies, and others. This article will explain how to create and maintain the proper home environment for many of the commercially sold brackish water fish.
Why should you chose a brackish aquarium? Brackish water aquariums, as mentioned above, are unique. They are usually conversation pieces and allow your aquarium to be different than most others. They also, despite some myths, are easy to maintain since the fish from brackish waters are designed to withstand frequent salinity and water parameter changes unlike both fresh and saltwater fish.
Equipments :
The equipment you will need for a brackish water tank is similar to a freshwater tank but with a few additions. You will need:
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Aquarium. Some articles claim that a 55 gallon or larger aquarium is required for brackish water aquaria but this is untrue. You could go as low as a 10g or even a 5.5g. The recommended set-ups later in the article may help you chose tank size.
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Filter. The best filters for a brackish tank are hang on the back mechanical and bio-wheel filters or canister filters. Undergravel filters will not work properly with a sand substrate. For aquariums larger than 20 gallons, you should use 2 filters on opposite sides of the tank. You will want to have your water turned around 10 times per hour (so you would need a single 300gph filter or two 150gph filters for a 30g tank).
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Heater. Never go cheap on a heater. Submersible heaters are much better at spreading heat and are less likely to shatter. Make sure you get a heater marked for fresh AND saltwater use. You also need to make sure the heater is adequate in size. A rule of thumb is 5 watts of heat per gallon.
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Glass Top/Light Hood. All tanks should be covered and brackish tanks are no exception. Keep in mind, also, that brackish water evaporates faster than fresh water. If you plan on keeping plants, get atleast 1.5 Watts of light per gallon of water.
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Thermometer and Hydrometer. You will need the thermometer to keep the temperature and a hydrometer to measure the salinity of the water. A cheap swing handle hydrometer is fine for this situation.
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Substrate. Brackish water areas always are covered in a sandy, silty, or muddy material and I feel that sand is the best option for a brackish water aquarium. You could use marine aragonite, "Minerial Mud", or play sand (which can be found VERY cheap at hardware and home improvement stores). If you plan on keeping live rooted plants, you will need about a 1" layer of substrate (avoid larger layers as they can build up anaerobic spots) and for a fish only tank, a very thin layer is best.
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Marine Salt. I prefer Instant Ocean but most brands should work. AVOID Freshwater Aquarium Salt as this is not the proper salt to use in brackish or marine tanks (although it is fine in full freshwater tanks to fight off parasites).
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Water Condtioner. As with all aquariums, you will need a product to remove chlorine and chloramine from your tap water before placing it in the tank. Make sure the product is listed for both fresh and saltwater use.
Once you have all of this equipment, you are ready to set up a brackish water tank. The question now is: What fish should I get?
Recommended Set-Ups :
Brackish water fish do not all come from the same brackish waters. Some are found in the slow flowing estuaries and mangrove swamps while others are found in the fast flowing saltier ends of rivers. Fish, as you would expect, do better in as close to natural condtions as possible and therefore I have split the brackish category into 3 setups.
Set-Up 1: Estuary
Estuaries are most people's idea of where brackish water occurs. Estuaries are slow-moderate flowing and the aeration from your filter(s) should be adequete. Although there will be set-ups for smaller tanks down the line, an estuary tank is best with a quite large aquarium.
Estuary Set-up:
Inhabitants:
More than 125 gallon tank size
(6) Monos
- - - OR - - -
(5) Scats
- - - OR - - -
(6) Sebae Monos
- - - OR - - -
(5) Colombian Shark Catfish
Monodactylus Argenteus
Mono
Distribution: Africa, Indonesia
Adult Size : 9.75"
Diet : Omnivore
Min. Tank : 75 Gallons
Temperament : Semi-Aggressive
Strata:Middle
Scat
Scatophagus Argus
Distribution:Indonesia, Phillipines
Adult Size:11.75"
Diet:Omnivore, greens needed
Min. Tank:75 Gallons
Temperament:Aggressive
Strata:Middle
Sciades seemanni
Colombian Shark Catfish
Distribution:Pacific Coast, Colombia
Adult Size:11.75"
Diet:Omnivore
Min. Tank:75 Gallons
Temperament:Peaceful but eats small fish
Strata:Bottom, Middle
Plants:
Plants in this tank are very likely to be eaten. Java Fern and Java Moss MAY survive. After raising your specific gravity over 1.015, these plants will begin to die off and they should be replaced with marine algae such as Caulerpa.
Temperature:
80-82 F
pH Level:
7.5-8.5
Decoration:
Sparesly decorate with rocks and branchy driftwood (that has been cured to prevent leaks).
Salt:
All of the fish listed above migrate down the estuary to the ocean when they are several years old, so you will have to mimic this the best of your ability. Buy all of your inhabitants young and start this tank with around 2 tablespoons of marine salt per gallon of water. Every 6 months, add an additional tablespoon of salt per gallon of water during water changes. Stop when you are adding about 7 tablespoons of salt per gallon of water or when your hydrometer measures a reading of 1.020-1.025. This should take about 3-4 years and they should not be rushed into full marine water. Keep in mind NOT to add the salt directly to the tank.
Set-Up #2: Brackish River
Towards the end of the outward flowing rivers that empty into estuaries, there is brackish water. These are fast flowing regions and you should attain an additional powerhead directed to flow to the side to provide increased aeration and movement. These set-ups are a great home to mollies, gobies, puffers, and silversides and (in the case of Bumble Bee gobies) can be as little as 5.5 gallons.
Brackish River Set-up
Inhabitants:
More Than 5.5 Gallon Tank Size
(3) Bumble Bee Gobies
More Than 10 Gallon Tank Size
(3) Mollies
(1)Knight Goby
- - - OR - - -
(3) Mollies
(3)Bumble Bee Gobies
- - - OR - - -
(3) Glassfish
(1) Knight Goby
- - - OR - - -
(3) Glassfish
(3) Bumble Bee Gobies
More Than 30 Gallon Tank Size
(3) Mollies
(6) Celebes Rainbows
(7) Bumble Bee Gobies
- - - OR - - -
(3) Glassfish
(6) Celebes Rainbows
(7) Bumble Bee Gobies
- - - OR - - -
(3) Mollies
(4) Glassfish
(2) Knight Gobies
(3) Bumble Bee Gobies
- - - OR - - -
(2) Green Spotted Puffers
(5) Bumble Bee Gobies
- - - OR - - -
(2) Figure Eight Puffers
(5) Bumble Bee Gobies
- - - OR - - -
(2) Orange Chromides
(2) Knight Gobies
More Than 30 Gallon Tank Size
(3) Mollies
(3) Glassfish
(2) Celebes Rainbowfish
(2) Knight Gobies
(5) Bumble Bee Gobies
- - - OR - - -
(3) Green Spotted Puffers
(7) Bumble Bee Gobies
- - - OR - - -
(3) Figure Eight Puffers
(7) Bumble Bee Gobies
- - - OR - - -
(3) Orange Chromides
(3) Knight Gobies
(6) Bumble Bee Gobies
- - - OR - - -
(3) Ceylon Puffer
(3) Mollies
(5) Bumble Bee Gobies
More Than 30 Gallon Tank Size
(3) Siamese Tiger Fish
- - - OR - - -
(3) Mollies
(5) Glassfish
(10) Celebes Rainbowfish
(4) Knight Gobies
(8) Bumble Bee Gobies
- - - OR - - -
(8) Green Spotted Puffers
(10) Bumble Bee Gobies
- - - OR - - -
(8) Figure Eight Puffers
(10) Bumble Bee Gobies
- - - OR - - -
(6) Orange Chromides
(4) Knight Gobies
(8) Bumble Bee Gobies
- - - OR - - -
(6) Ceylon Puffer
(6) Mollies
(10) Bumble Bee Gobies
- - - OR - - -
(3) Targetfish
Plants:
Anubius, Vallisneria, Hairgrass, and Java Fern are best suited to the currents of this tank although plastic is probably the best choice.
Temperature:
80-84 F
pH Level:
7.5-8.5
Decoration:
Decorate with taller plants in the background and shorter ones on the side. Add one or more rock cave for your gobies. Anubius and Java Fern should be attached to the rock cave(s).
Salt:
Around 1-2 tablespoons of marine salt per gallon of water or a specific gravity of 1.005-1.010 will be adequate for the full lives of most of these fish. Green Spotted Puffers prefer saltier conditions with around 3-5 tablespoons of marine salt per gallon of water or a specific gravity of 1.010-1.020.
Mangrove swamps are slow flowing waters covered in floating plants and mangrove roots. These set-ups are designed to be part land, part water. For this reason, it is recommended to use a 55g or larger aquarium so that there is enough swimming room for the fish. The best filtration method in this case would be a cannister filter with enough tubing to extend into the water.
Set-Up #3: Mangrove Swamp
Brachygobius Xanthozona
Bumble Bee Goby
Distribution : Southeast Asia
Adult Size : 1.75"
Diet : Carnivore. Needs live food.
Min. Tank : 5.5 Gallons
Temperament : Aggressive
Strata : Bottom
Stigmatogobius Sadanundio
Knight Goby
Distribution:Southeast Asia
Adult Size:3.25"
Diet:Omnivore
Min. Tank:10 Gallons
Temperament:Peaceful
Strata:Bottom, Middle
Telmatherina Ladigesi
Celebes Rainbowfish
Distribution:Celebes Island
Adult Size:3"
Diet:Omnivore
Min. Tank:10 Gallons
Temperament:Peaceful
Strata:Middle
Poecilia sphenops, Poecilia latipinna
Black Molly, Sailfin Molly
Distribution:Southern USA
Adult Size:Male 4", Female 4.75"
Diet:Omnivore, greens required
Min. Tank:10 Gallons
Temperament:Peaceful
Strata:Middle, Top
Parambassis ranga
Indian glass fish
Distribution:Thailand, India
Adult Size:3.25"
Diet:Omnivore.
Min. Tank:10 Gallons
Temperament:Peaceful
Strata:Middle
Mangrove Swamp Set-up
Inhabitants:
More Than 55 Gallon Tank Size
(2) Archer Fish
- - - OR - - -
(3) Mudskippers
(3) Fiddler Crabs
More Than 125 Gallon Tank Size
(4) Anableps
- - - OR - - -
(4) Archer Fish
- - - OR - - -
(6) Mudskippers
(6) Fiddler Crabs
Plants:
Mangroves are the obvious choice for this tank. They should be planted on the edge of the water and on the land section. As for aquatic plants, since most are not readily available, plastic plants are best but you could try Java Moss, Java Fern, Cryptocorne Bekketti, Hairgrass, and Vallisneria.
Temperature:
82-86 F
pH Level:
7.5-8.5
Decoration:
The usage of tree root ornaments would be ideal in this setup. Many mangroves and partially subdued lighting will make this tank more realistic. These swamps usually also have floating plants covering the surface but most of these plants are not available commercially (although you could try java moss).
Salt:
Around 3 tablespoons of marine salt per gallon of water or a specific gravity of 1.010-1.015 will be adequate for the full lives of these fish
Mudskipper
Periophthalmus Spp.
Distribution:Southeast Asia, Australia
Adult Size:6"
Diet:Carnivore. Needs live food.
Min. Tank:55 Gallons
Temperament:Semi-Aggressive
Strata:Bottom. Needs dry land.
Uca crassipes
Fiddler Crab
Distribution:Southeast Asia, Australia
Adult Size:1.25"
Diet:Detrivore.
Min. Tank:10 Gallons
Temperament:Semi-Aggressive
Strata:Bottom. Needs dry land.
Maintenance :
Once you have set-up your tank to your desired brackish set-up and have fully cycled the tank, you will have to learn a schedule of maintenance to care for your tank.
I am a firm believer of frequent water changes. I recommend cleaning 15% of your water once a week. When adding the replacement water, make sure you add about the same dosage of salt as before (unless you are running the estuary set-up, in which case the dosage increases every 6 months). It is not necessary to check with a hydrometer since these fish are naturally familiar to varying levels of salinity but you should be within a good range of accuracy to prevent shock.
One to two times a week, you should stir up the sand with the back end of a fish net. After stirring, turn the fish net to scoop the debris you have stirred up into the net. If you are using 1" of sand or more, this stirring also helps prevent anaerobic spots from forming (these spots can release deadly gases into your tank).
Feeding should be done atleast 2 times daily. All of the forementioned brackish set-ups are recommended to have warm water (atleast 80F) and this increases the fish's metabolism, causing them to eat more food and grow faster. So, 2-3 feedings a day is much preferred, with 3 being optimal. Many of these fish (mollies, monos, scats, knight gobies) require some vegetable matter in their diet and puffers should be fed snails on occassion to reduce the size of their "beak".
Conclusion :
Once you have set up your brackish water aquarium and have become accustomed to the required work, you will have created an entertaining and low maintenance aquarium with some of nature's most unique and wonderous creatures.
courtesy to : www.badmanstropicalfish.com