Welcome to the world of saltwater aquariums! This guide will hopefully get you from wanting a saltwater tank to owning one.
1. Buy a tank
Generally speaking, the shallower and the bigger the tank the easier it is to maintain, up to a certain point at least. A drilled tank with a drain or overflow and asetup is a big plus. The roomier the sump the better.
There are many reasons to get a "long tank" vs a "tall" tank. Fish swim horizontally for the most part, rather than vertically, with the exception of seahorses and a few other fish. If you are considering a reef tank, the deeper the tank the more light you will need to penetrate to the bottom. The additional light source might cause too much heat, necessitating a chiller. Chillers themselves are expensive and consume lots of electricity. Save yourself the headache and start with a standard "long" tank. You may have more evaporation concerns, but they are easily dealt with automated top off systems or just a bit of care from you.
If something goes wrong in the tank, the water conditions will change. In a larger tank these conditions will be diluted over more gallons rather than less, and the impact to the tank's inhabitants will not be as severe. The maintenance of a "nano tank " (tanks under 30 gallons in my book), can be difficult because there is little room for error on the part of the aquarist. At some point a huge tank can become an overwhelming task as well. A "40 gallon breeder" or bigger should give a beginner enough room to make a few mistakes. Adding a sump adds water volume, and a place for additional filtration which is always a good thing.
2. Basic Filtration
Hang on Back Filters - We have used hang on the back (HOB) filters and find they are a reliable way to remove ammonia and nitrite from your tank. Get one with a biowheel, and make sure to regularly clean the filter pads, and run carbon. Never clean the biowheel. The point of hang on the back filters is to provide a bacterial safeguard to keep your tank ammonia and nitrite free. They are also a good backup plan should your sump's return pump fail if the water gets too low in it for example. However, they accumulate salt and have to be cleaned off, and they do not generate enough flow for the system by itself.
Sumps - If you have an overflow that leads to a sump, which is tank below your tank that overflow water drains into, you can utilize filter socks or filter pads (often called "filter floss" in the hobby) to remove debris and detritus from the draining water. After that, most people will utilize some sort of surface area filtration whether it is bio balls or rubble rock that can serve as a home to denitrifying bacteria that removes ammonia and nitrites from your tank. Combining a sump with your display tank is one of the best decisions you can make, as it provides a place for filtering algae and rock to purify your water, it adds water volume, and it can provide a place to grow live food for the display tank. It also allows you to operate your mechanical filters removed from the display view.
Protein Skimmers - A protein skimmer uses tension from its vortex chamber (looks like a whirlpool) to trap proteins in what is called skimmate, which is basically organic waste floating in your water. This foamy junk collects in the cup at the top, and when the cup is full, rinse out the foam and you are done. This removes proteins that were small enough to pass through the filter sock or filter pad.
Deep Sand Bed - Aquarists who want to replicate the filtration power of the ocean's vast sandy bottoms can create their own if they design a sand bed that has roughly 4 inches or more of sand in a remote tank that is plumbed together with the main system. The point of this is to cause an area deep within the sand that is anaerobic, meaning it receives little oxygen. Unlike the surface (aerobic) bacteria in your tank that remove ammonia and nitrites from the water, anaerobic bacteria changes potentially harmful nitrates to safe atmospheric nitrogen. Just be careful you don't create a sand bed that is too deep, or too fine, or you could develop a hydrogen sulfide pocket that can harm your tank. These pockets form in areas that are totally devoid of oxygen and stagnant. You will know it if you should ever disturb one of these dead spots, they have a distinct sulfur/rotten eggs smell to them. Good cleaners for these deep sand beds are ceriths and nassarius snails. Larger sand sifters like conchs should be avoided, as they would like disturb too much sand and introduce unwanted oxygen to lower layers.
Fluidized Sand Beds - Today other media is used in addition to sand, but basically these systems utilize the amazing amount of surface area found on small particle sand by forcing water to rise up through the sand before it passes back into the display portion of the tank. Because the sand is being regularly churned with oxygenated water, this filtration method removes ammonia, nitrites and breaks down debris, it does not remove nitrates like a Deep Sand Bed.
Under Gravel Systems - Once popular, these systems that use air to move water over bacteria covered gravel is rarely used in modern reef aquaria, except for in culture operations, or in species specific tanks.
3. Add Sand
There is little difference in the quality of life in dry base sand and bagged live sand. There is nothing magical about bagged "live" sand, it is just sand with some bacteria on it. There is bacteria everywhere in an aquarium, it shouldn't influence your decision. Since it all has to be washed, we think dry sand is easier to handle because you can wash it with freshwater without losing the "value'. If your local store has live sand in a vat or tank though, that is different, in addition to bacteria it may have worms, copepods and other microfauna that are fun to have in a tank and aerate the substrate. You wouldn't want to wash that sand, and it would be a good addition to your aquarium. If it is under light it may have coralline algae too. It shouldn't be attached to the store's holding system though, and it should be free of debris. You don't need gunk to establish life in your tank, there will be plenty of it soon enough anyway, so try to get the cleanest source of seed sand possible. Never buy used sand from someone's aquarium, and if you buy a used aquarium consider replacing the sand, it will have a lot of junk in it.
If sand like this is not available to you locally, you can introduce microfauna by swapping a handful of sand with a fellow aquarist, (less is more, an established sand bed is likely to have debris trapped in it), or simply by purchasing a live rock and placing it in the aquarium. Microfauna establishes quickly on uninhabited substrates, you don't need to be too concerned about it. Just be patient and try to forget about them and they will be there before you know it. What you will want to focus on is the contents of the sand, the look and texture because that is what you will be stuck with for years.
You will want to stay away from silica based sands which tend to have more free silicates available and cause chronic diatom issues when the sand bed is disturbed. Diatoms by the way, are a brown powdery algae that appears in almost every tank, but you don't have to encourage it. Aragonite based sands are preferred because of the amounts of silicates that are leached are relatively low, and the calcium based sands look natural in a reef environment. Crushed shell substrates are also calcium based, and make a suitable substrate if you like the look of them, but may trap detritus. Black Sand usually has some volcanic origin, and while it looks great the first month or so, it will require diligent maintenance in the long run as it tends to show detritus. Additionally, burrowing critters tend to disfavor black sand substrates.
The most popular choice in the hobby currently is the off white aragonite based sands. There are almost as many shades of white sand in the hobby as you will find in a home depot paint department, I leave that up to you. Aragonite sands usually originate in the Bahamas, where dredging for calcium carbonate glass and factory scrubbers offer the hobby an inexpensive and reliable deep water source for aragonite sand that has been made up by calcium precipitation, the skeletons of foramniforens and coral rubble that has been worn down over the years. There are other types of aragonite based sands though, such as those created by the calcified Halimeda, which in my opinion makes the best substrate for macroalgae planted tanks. (Other aragonite based sand are suitable for macroalgae, but black sand and crushed shell aren't).
Now that you have settled on a suitable calcium based sand, it is time to settle on a texture. In general, finer grain sand will provide more surface area for filtration for bacteria to colonize while keeping debris at the surface where it is easy to siphon. It tends to hold rooting plants well too, however it tends to cloud the tank if it is disturbed. You should also be aware that fine grain sand substrates if made too deep might cause anoxic pockets that trap potentially harmful hydrogen sulfide. These dead spots form where there is there no oxygen and very little if any water transfer and some decay. (Whereas as a healthy anaerobic sand bed has very little oxygen, but regular water transfer, even if it is just a trickle). As a rule of thumb a fine sand bed should be no deeper than 3 inches.
Coarse sand tends to trap debris and doesn't have the surface area of fine sand, but because it does not get compacted it can be made much deeper, and coarse sand can be mixed in with finer sands to help facilitate water transfer if the aquarist desires a lot of sand. It also has the lowest tendency to cloud the water when disturbed.
Depth will depend on whether or not you want to plant macroalgae, whether you be keeping corals that creep along the sand, burrowing fish and what size the tank it is and how much of the display you want devoted to sand. Some people ditch it altogether and go bare bottom because it is easier to siphon. To each their own, just be aware of the anoxia problem discussed earlier. 1-2 inches is fine for most tanks.
Now that you have the desired depth, texture, content, and look down, you only need to rinse the sand in a bucket by stirring it quickly in a circle and then pouring out the silt and debris that is suspended in the water. You will want to do this for any sand that you received pre-packaged, it just makes sense, but you may want to skip it for sand that was packaged live from a local source, as you may pour out microfauna. Washing the sand you get in most cases will reduce the amount of diatoms you have to deal with and will reduce the amount of cloudiness you experience as there tends to be silt in just about any sand source.
A Note on Mud - If the purpose of purchasing mud is to maximize the growth of macroalgae and seagrasses, I would try to get one that is calcium carbonate based sand that comes from a calcified algae source. Halimeda, pencil caps and other rooted algae grow really well on their own skeletons, (called halimeda hash), and seagrasses can create very deep and robust root systems through the coarse newly formed hash halimeda down and into the finer pulverized substrate that has been weather beaten down over the years. The more hash in your mud substrate the better. Black mud products are not necessary, and are not found in the nicest seagrass and macroalgae beds in the ocean.
4. Adding Rock
Today the aquarist has many different options to choose from when it comes to selecting rock for their aquarium. There are basically 4 different characteristics that you want to keep in mind when selecting rock; looks, composition, porosity and degree of life.
Looks - You first want to make sure you like the general shape or style of the rock. The surface of the rock will change color as it is colonized with life so you should try to not let that weigh in on your decision, unless of course you are purchasing live rock with particularly good coralline algae. There are a lot of different types of rocks, and even large coral skeletons that can be used to form the aquascape you want. Take some time and be creative with it and you will get the more enjoyment of the time you spend on this hobby. However, if you can find a rock with lots of curves and crevices that you like the look of that will help, as these features give ammonia and nitrite removing bacteria more surface area to colonize.
Composition - There are a surprising amount of surfaces that are suitable to use in an aquarium. However, it is the calcium carbonate based rocks that are most popular in the hobby for their natural appearance, recruiting ability, porosity and buffering properties. These rocks are made up of limestone or coral skeletons and are the natural substrate most reefs are built on. Other materials like glass and volcanic rock, lack porosity, which is important in de-nitrification. Concrete based man made rocks had popularity at some point, and are safe to use after extensive curing.
Porosity - When you are choosing your liverock make sure to look for rock that is light for its size. This will indicate the rock has channels or pores inside of it. These pores are usually created when the animals that made homes in the rock over the years were vacated, or by low ph water that dissolved tunnels through the limestone. It is within these tunnels that water is slowed down, oxygen levels drop and anaerobic bacteria establishes itself to reduce nitrates in your aquarium. The accumulation or availability of nitrates in your aquarium will help to fuel nuisance algae breakouts, and cause you to have to change the water more often than normal. By choosing porous rock from your aquarium you can save yourself some additional water changes, and keep sensitive livestock happy.
Degree of Life - There are many different grades of liverock in the hobby, here are a few of the most popular, starting from the least amount of life to the most:
Dry Rock - To its benefit, dry base rock is inexpensive to ship,contains no unwanted hitchhikers or algae spores and can be arranged leisurely in an empty tank. It takes some time to colonize with life though, and usually some liverock or coralline shavings have to be introduced to begin colonization. Dry base rock is usually supplied through a quarry, or manmade. However, sometimes it is crow barred from a living reef and allowed to dry out. Personally, I feel like this type of "Economy Rock" is a waste of a resource, and that if a living reef has to be removed it should at least be cared for.
However it is was made, the base rock can either be cleaned, or include organics on it. If it includes organics it needs to be cured. If you can, try to get rock that is devoid of organics and free of cycling or curing. Anything that has been cycled or cured in saltwater will have to be re-cured and cycled again on arrival because of the die off of microfauna that occurs in transport. We introduced a type of organic free base rock a few years ago, and now there are other organic free options emerging on the market as well.
Shipped Live Rock - Liverock that arrives to you after being recently in transport will have a good degree of life, and die off on it. It should be cycled, and may need to be cured. Cycling the rock consists of leaving it in the tank until the die off deteriorates and the nitrogen cycle is completed. Curing is a process in which nuisance life is picked from the rock and it is kept in a tank in the dark until nuisance algae and turfs die off and are removed from the rock. In any event because of the die off associated with shipped rock it needs to be prepared before it can be added to a system with live animals in it. The longer the trip, the more die off your rock will experience.
Fresh Live Rock - Fresh liverock that is purchased from your local pet store that was holding the rock in a cycled tank can usually be added safely when you get home. You may want to cure it though if you don't like the hitchhikers found on the rock and ask the pet store owner if the rock is safe to add to an established tank before assuming the rock has been cycled/cured.
Pests - It is important to make sure that you closely examine your rock for surprises. There are tons of rock in this hobby that have difficult to remove algae species and like bryopsis and annoying inverts like aiptasia living on them. The best way to handle these pests is to never let them in your tank in the first place.There are both algae and invertebrate pests you will want to watch out for.
Amount of Rock - As a general rule for filtration, 1.5 pounds of rock per gallon should be provide enough surface area for aerobic bacteria and a fair amount of denitrification capacity. You may want to go with a little less if you want a minimalist look, but try to remember to find other ways to add surface area to your tank, like a sand substrate, or a mechanical filter system.
5. Add Water
Get some aquarium salt, and add the right amount of water- mix in a bucket. For best results use RO/DI water, which contains zero dissolved solids. (Your tap water is not pure H2O, but RO/DI water is close, and so is Distilled Water.) You can make your own if you buy a RO/DI system, or by purchasing the water from your local pet store. To add salt it is usually easier, (and more accurate), to weigh the salt out rather than to fill a bunch of cups of it. Read the directions carefully on the bag, and try to get the specific gravity (salinity) at 78 degrees to be around 1.024. (The specific gravity will change with the temperature, so be mindful of this). To measure the specific gravity you will need a hydrometer or a refractometer. Refractometers are worth the extra cost, because of reliability and accuracy.
When you add the water, do so slowly so as not to disrupt too much sand, and the inhabitants. Pouring it over a bucket lid so as to displace the water. A small pump can also be utilized to move the newly mixed water into the aquarium.
6. Add Current
When the sand settles turn on the filter, and get the water current going. Check each area in the tank to make sure their is water flow in every area. If need be get a powerhead or two to add current to all the places in your tank. Current usually comes from one of two places, from either a pump that lifts water from one place to another, or from a powerhead that constantly pushes water within the aquarium.
Pumps - Systems with a refugium or sump utilize a pump to lift water from this separate location into the main display where it usually drains through an overflow back down to the sump, pulled by gravity. Sometimes siphons are used, but tend to be more flood prone. Pumps are used when pressure is needed, in fact if you don't have enough pressure coming from your return pump, the water from your sump or refugium might not make it to the display portion of your tank. To avoid this scenario make sure to check the head loss calculator that is usually available from the vendor of the pump prior to purchase. It will let you know how many gallons the pump is rated for at what height. The re-directed water can be piped, valved and LocLined to provide current where it is needed most.(Loc Line is the name of a company that produces products that allow you to divert water flow from a return pump).
Hang on Back Filters - Utilize a weak pump to draw water through a series of mechanical filtration media before allowing it to gently return to the aquarium. The returning water helps to agitate the surface of the aquarium, which helps to ensure adequate oxygen levels are maintained. Because the water falls to the aquarium though, it is hard to use a hang on the back filter to create current for fish to swim in throughout the aquarium, and it is even harder to keep coral happy.Because of this they are almost always augmented by powerheads.
Powerheads - Powerheads turn an impeller to push water gently and at high volume over a large space. They have lower velocity and pressure than a pump, but turn far more gallons per hour usually for the cost, and more importantly create natural currents in the aquarium.
Air Stones - Because of the salt buildup they cause on nearby surfaces, air stones are generally not favored in the saltwater aquarium hobby outside use in culture applications.
7. Adding Light
There are many different lighting options available to the aquarist these days. Here is a short list of the type of bulbs you will come across in the hobby:
Standard Fluorescent Bulbs (T12)- Only used for utility purposes or in fish only tank kits. Can grow macroalgae and some low light requiring corals, but they are fairly weak.
Compact Fluorescent Bulbs- These inexpensive bulbs used to be the state of the art twenty years ago. They are still good for lower light demanding soft corals, some LPS corals and macroalgae. 60-80 watts over a 20 gallon long aquarium is our standard "ideal" range to carry the majority of algae and saltwater plant species we carry. Compact fluorescent give good light coverage, with fairly even lighting, although it tends to be the brightest in the center.
Metal Halide - Powerful lights that give off a good deal of heat and draw a great deal of electricity. These light should be fanned and given plenty of ventilation, as they run far more efficiently if they are relatively cool. These fixtures often give off intense light, but tend to spread light poorly, focusing most of it in a spot under the bulb(s). Still, you can get great results growing fast growing green algae with a 250 watt metal halide light over a 40 gallon breeder tank.You can grow just about any light demanding coral under metal halides, and because they tend to concentrate light in a certain area, corals that do not appreciate intense light can be placed on the corners of the tank away from the spotlight. Metal Halides give a shimmering light effect that no other light type truly replicates, and are my personal favorite for viewing.
T5HO - The HO stands for "High Output" and that is just what these powerful and efficient lights do. This established technology is preferred among reef aquarists because they give off relatively low heat, spread light well, and can be easily color customized. 54 watts of T5HO works well over a standard 29 Long aquarium to achieve strong growth results for the majority of soft and hard corals and almost all of the macroalgae species we carry. (Compare that to our recommendation of 60-80 watts of power compact lighting for 20 gallon long aquariums. The discrepancy is based on the assumption that your T5 fixture will have better reflectors as most do, the quality of your fixture is something to be mindful of when reading these recommendations).
LEDs - With endless customization possibilities, high output, low heat, long life, and low profile fixtures, it is no wonder LEDs became popular in the aquarium hobby. You should discuss any LED light purchase with the vendor, as the output per watt and the intensity of a certain fixture can vary dramatically and there aren't any good rules of thumb established for the market yet. The quality of the LED bulb can vary a good deal still, and you will want to stick with reputable vendors that are advertising the particular light for a reef aquarium if that is what you want to build. LED "light strips" are generally not made for photosynthetic growth, and are mainly for low light/night time viewing purposes. Another drawback to LED fixtures is the bulbs/diodes are hard to change as they lose color and fade over time. Faded lights tend to grow nuisance algae, and replacing them often requires replacing the entire fixture. So while LEDs do last long, when they go their replacement may mean the end of life for the fixture.
Hybrid Lighting - The newest fixtures to hit the market are a hybrid between LEDs and T5HO fixtures These fixtures typically have T5HO bulbs in the center with LEDs to supplement color and intensity on the flanks. These fixtures are fairly new, and haven't proven themselves yet at the time of this writing for long life. It will be interesting to see if the benefits of these fixtures offset the drawback of having a fixture with difficult to replace LEDs.
A Note About Color - Color refers to the Kelvin temperature of the bulb...for beginner purposes it is basically where the light spectrum of the bulb is focused around, the higher the number, the bluer the light, the lower the number the more yellow. Bulbs in the middle like in the 10k-14k give off a whitish light, a 6700k bulb is pretty yellow and a 20k bulb is almost completely blue. In addition to the fixtures, your light bulbs should be chosen with what you have in mind for the tank. It may be a little early for you to know what you want to achieve with the tank, but certain lights are better for certain purposes and this stuff isn't cheap so make up your mind already, or get an LED fixture that allows you to change the color.
Without getting into too much detail, here is a list of goals with suggested lighting color arrangements. If you ask around on the forums there will be 1000 people who will debate these choices, but this hobby is like that, it doesn't mean I am wrong. It means they are:
Eye Popping Coral Only - 20k only lighting setups have been known to color up zoas and other corals.They tend to make the tank look unnatural, and aren't very bright to the human eye nor in PAR levels. The amount of usable spikes on the photosynthetic light spectrum are relatively low with 20k bulbs,but they do tend to highlight the bright florescent light that high end coral collectors strive to improve. In a T5 or a LED setup they can be supplemented with 14k or other bluish light to add to PAR without sacrificing much color. Macroalgae tend do poorly in the long run under these lighting setups, with the exception of some species of red algae, most notably the coralline algae species and Halymenia. (Coralline is an type of algae by the way, there are hundreds of different species of coralline and none of them are related to the coral animals they share a similar name with.)
Normal Reef Tank Viewing - 14k lighting is probably the most pleasing range of color. It has enough blue to make colors pop, but there is enough white light to make the aquarium easily visible to the human eye.
Macro Algae Tank Viewing - Planted saltwater aquariums tend to look better and grow better with a color range that is warmer, 10-12k range is a good balance between the macroalgae and plant's needs and attractive viewing light.
Macro Algae Filtration/Refugium - Keep it simple here, go for maximum output per watt, and maximize the amount coverage along the usable photosynthetic light spectrum. What that means is use a warm colored grow light, and don't spend money on bells and whistles that have it change color as the day goes on etc..
8. Wait through the cycle
The nitrogen cycle that is. When organic material in your aquarium dissolves (Such as uneaten food, fish waste, etc...), it first turns into toxic ammonia. When it turns into ammonia a special kind of bacteria grows and devours it. If you are testing for ammonia during this time, (and you should be), you will see a steady ammonia increase and then a sudden drop off. The bacteria that consumes the ammonia will leave toxic nitrite as waste. Again, bacteria will form to consume the nitrite, and you will see a steady increase of nitrite, and then a sharp decline. Afterward you will see a buildup of nitrate. Nitrate is harmful in large quantities and helps nuisance algae to grow, so you will want to take care of it.(More on this below).
To start the cycle in this first place, throw a piece of food quality shrimp into your aquarium and remove it after a few days. Remember, do not add any living creature, (other than microorganisms), until the ammonia and nitrite in your tank drop to undetectable levels.
9. Taking Care of Nutrients in Your Tank
After your tank is finished cycling, you may notice a spike in your nitrate level. Perform a 50% water change to help reduce the nitrates. After that 10% of your water should be changed each week, for the remainder of your tank's life, unless conditions warrant additional water changes. At this time, it is safe to plant macro algae. (How to grow macro algae) Macro algae absorbs the same nutrients that nuisance algae needs to survive. By introducing competition for food you will be stabilizing water parameters and helping to keep your tank clean. You should also begin to see your rock pulling down nitrates. Phosphates may become bound in the rock, but will leech out at some point; so it is a good idea to have something to deal with it. If not, you may get a cyano bloom when the tank gets older because cyano thrives on phosphates, particularly when there is a N:P imbalance - but that is a subject for this article .
At this point the aquarium is up and running. Now to take care of nutrients and improve the quality and stability of your water. Check under the information tab on the menu bar under our logo for articles regarding this and related subjects.