II. Starting a Reef Aquarium – Initial steps and startup
This article discusses Live Rock, Cleaning Crews, Starter Fish, and Coral
Once the tank is filled and the system has been running at a proper temperature we can begin to build our reef. Begin by shutting down the filters and pumps in the system, gather a few buckets with which to remove and hold water before it is displaced and on the floor. Remove water from the display dropping the tank level by about 6", you may need to remove later. Next place a layer of base rock directly onto the bottom of the aquarium to assure the stability of your reef structure over time.
Slowly lower a bag of live sand into the water until the end seam of the bag lies on the bottom of the tank then carefully cut the bag open along this seam. Holding the bottom corners of the bag, slowly remove the bag from the water and the sand will gently pour onto the bottom of the tank, working from one side of the tank to the other will help with even distribution. With the bag out of the way work the sand to the sides of the tank and around the base rock layer so that it is a consistent depth throughout the tank. If you have not already done so since initially starting, your tanks water level may be closer to the starting level and it may be a good time to remove some more water before moving on to adding your live rock.
Live Rock
Live rock is the skeletons of long-dead coral transformed by time and many complex geological processes into calcium based rock. Live rock ranges from exceptionally porous to incredibly dense rocks of arbitrary shapes and sizes to spectacular branching shapes and flatter shelves depending on the location of origin however the best option by far for live rock is farmed live rock. The farmed live rock varies vastly; some sources will harvest bedrock from dried out reefs and place them in the ocean for several months or store them in large pools with established live rock to "incubate". Some sources may even use a combination of plasters and sand to create completely artificial rock and then allow it to incubate, again either in man-made pools or ponds or in the ocean. After several months the various bacteria, algae, sponges, and micro-fauna will begin to colonize the rocks and the rocks at this point are considered live.
Take the precaution of wearing puncture resistant gloves before handling live rock and assure that the pieces stay in the high humidity packaging it comes shipped in. If mail order rock is used the heating and humidity inside the shipping packaging will easily keep the live rock viable for up to 48 hours in transit, if left unopened. Alternatively, you may use buckets with enough salt water to submerge the pieces to sort and store them while arranging your reefscape.
Layer the live rock on top of the base rock structure. Be mindful to allow a clearance between your rocks and the walls of the aquarium to allow for ease of cleaning and adequate water flow around the tank. Care should be taken to not stack the live rock so tightly as to create complete flow obstruction through the rocks but tightly enough to remain stable.
To secure your live rock to the structural base rock you may use two-part epoxies. These come in a tube form consisting of a core of adhesive filler surrounded in a hardening agent. A small even piece is cut and kneaded until the color is uniform, this is applied to the surface of the base rock. Live rock is then pressed into the epoxy footing and left to cure. Epoxy takes several hours to cure but this can be done underwater, it is best used to hold pieces in place and prevent lateral shifting but is not ideal for supporting rocks against gravity. More intricate reefscapes featuring arches and shelves can be constructed with a skeleton of PVC to which rocks can be secured using zip-ties. It will stick out at first but in time algae will cover the surfaces and it will become camouflaged.
You will likely create turbidity while arranging the rocks and thus it may be difficult to see your progress as you are building. In the coming days, the tank will settle and you will be able to make small adjustments here and there as needed. Take caution not to upset the structural base rock as you adjust the live rock above as other pieces may be displaced by this resulting in collapse. Ultimately, focus on getting the general shape or concept you are aiming for and then leave it for a few days, you may find that aspects you did not like are not as critical as initially imagined and that you are happy with the arrangement as is.
The “Modern” Nitrogen Cycle
The nitrogen cycle is a common moniker for the colonization process of various anaerobic bacteria such as Nitrosomonas and Nitrobacter. These bacteria convert toxic waste products into less harmful byproducts through their metabolic processes. In the past, this process was long and arduous. Sacrificial lambs, such as the inexpensive Damselfish or even freshwater Mollies were introduced into barren tanks. They would swim in their own waste until the bacteria formed. Over the course of four to six weeks, the aquarist would monitor the ammonia, nitrite, and nitrates of the tank watching for the spike and fall of each level. During this time the fish may develop health problems as a result of exposure to waste buildups.
Nowadays there are several bacterial cultures commercially available to consumers. This eliminates the "cycle" and allows a tank to be established almost instantly after filling. It should be noted that these products are all based on the principal of seeding the bacteria with live culture. This means that without nutrients to feed the bacteria they will die off. When using live rock there is a level of oxidation that occurs and a small fraction of the life on the rock may die in transit. The attrition of these organisms will also have an effect of spiking the waste level, however, live rock is loaded with the bacteria found in many "instant cycle" products thus adding more is moot.
This means that you may choose to cycle your tank by first adding live rock and monitoring the tank watching the spikes until cycled, or forgoing live rock all together you may add an "instant cycle" serum to the tank and a couple durable fish such as clownfish. Any of these methods will successfully cycle your tank. I prefer using live rock and waiting as the more natural approach has lower inherent risk, however, start to finish setting up in an afternoon has become more commonplace and there does not appear to be any drawback to these modern "instant cycle" serums.
Cleaning Crew
If cycling the tank with live rock, you will notice algae, sponges, crustaceans and even bacteria colonizing the rocks, sand, and glass of your aquarium. During the cycle, do not fret with keeping the rocks free of algae, I frequently will leave even the back and sides of aquarium untouched, cleaning only the front viewing panel. Once cycled however I leave cleaning of the rocks, sand and the other three panels to the "cleaning crew". A cleaning crew consists of specialized Invertebrates evolved to survive by eating the various algae and detritus that accumulate in our tanks.
A cleaning crew offers a plethora of options, all with their various benefits. While there are no real guidelines for composition, you will want a variety to assure each niche is addressed and none becomes overcrowded. The different niches to think about as implied above are the glass, substrate and rock surfaces. Most snails will address both the glass and rock surfaces; however, the Nassarius snail is the best candidate for keeping sand surfaces clean and free of detritus. Hermit crabs excel at cleaning the cracks and crevices along the rock surfaces and will greedily munch up and extra food that lands nearby. Outside of the various snails and hermit crabs which as a whole can easily serve as a cleaning crew on their own, there are other options including starfish, urchins, sea cucumbers, crabs, and more.
I recommend starting with an assortment of a half dozen snails and a half dozen hermit crabs for every 10 gallons of aquarium volume. You may need to add more than this to obtain the desired effect but be conscious not to create too much competition for food. Additionally, hermit crabs will fight over shells and snails may fall so that they can not right themselves. These unavoidable losses mean that your cleaning crew will need to be restocked periodically, usually once every few years. Lastly, all invertebrates are sensitive to pH, salinity, alkalinity, and ammonia so be certain the nitrogen cycle is complete and you are maintaining the ideal ph of 8.0-8.3 and salinity of 32-35 ppt.
Starter Fish
With your newly filled tank, or, with your tank that is maturing into its first months of age, it is time to add some finned fauna to add some color and movement to our reef scape. While there are hundreds of breathtaking fish to choose from, some fish, such as angelfish become very territorial once established in a tank and will make other additions later much harder. Some fish like the coveted Mandarinfish have a specialized diet of live food that can only be provided in a very large very mature tank. These are great examples of fish that are often seen and immediately desired but that do not fit the bill of a "starter fish".
Starter fish should be fish that do not become too territorial, as to allow other fish to not be bullied and harassed when added later. Stress from bullying can lead to sickness or death of new additions. Additionally, the fish that are added now should not be too fussy as to make the tank too much work to keep maintained. These two factors limit the ocean of options down fairly significantly, however, there are still many areas where the inexperienced may be lead astray. For example, the sturdy Damselfish is incredibly durable and capable of surviving any mishaps that a new reef keeper may experience. Damsels are brightly colored, active and the relatively small size at purchase will often quell aquarists into a false trust. Four years later this one inch bright blue active fish has matured into a 6-inch drab black fish with a temper to boot.
To give examples of fish that make excellent starter fish, we can look to the damselfish' sisters. The Chromis possesses the same color and often keeps it vibrant into adulthood, additionally, it has a placid and even timid demeanor meaning it is less likely to become territorial as time goes on. Alternatively, the common clownfish is by and large captive bred and raised. In many ways the flagship of the aquarium trade, serving as mascot, icon and the single most recognizable fish in the industry, the clownfish also makes a great choice for starting a tank. While clownfish may grow territorial they are not pelagic fish and instead claim a small area of the rocks as their home and spend their time defending a small "no-fly zone" instead of outright tank warfare.
Starter Coral
Similar to your first fish introductions you will want to make extra consideration for your initial coral purchases. Corals have varying levels of aggression and growth, a deceptively small coral colony of the right species may display long sweeper tentacles that serve as a defense against encroachment. Many corals secrete mucous that are toxic to other coral and stunt the growth or outright kill nearby colonies. Other corals, such as the popular Xenia and Zoanthid/Palythoa coral expand and colonize so rapidly that they leave scarce room for future additions. Fish you intend to add later may prefer to snack on some coral while completely ignoring others meaning this too should be considered.
Additionally, it is important for me to define aggression levels in coral before describing my picks for "least" aggressive starters as this is largely a subjective matter. I consider almost all living organisms capable of defense in some capacity, that said I do not consider necrosis as the result of direct contact between two colonies as aggression. Aggressive coral, in my opinion, employ a mode of preemptive territory clearing that extends far beyond reasonable accommodations, for example, the long sweeping tentacles of Galaxea. Moderately aggressive coral, on the other hand, may be accommodated by maintaining a perimeter around the coral to prevent their much smaller sweeper tentacles from reaching neighbors as with frogspawn or hammer coral.
This leaves the least of aggressive coral. These are coral that can be kept in relatively close proximity to other coral colonies with little or no negative effect on neighbors. One of the least aggressive coral I have found is leather corals. This is because their primary defense is a toxin secreted directly into the water. With modern filtration and carbon, these toxins are quickly filtered and rendered harmless thus meaning the only consideration is to assure there is no direct contact with neighbors. Second in aggression level would be Acanthastrea and Echinophyllia. Both Acanthastrea and Echinophyllia coral are considered Large Polyped Stony Corals but unlike many of other coral in this group, they have more diminutive tentacles and slower growth rates compared to the above-described leather corals.
Care should be taken to investigate the corals' primary mode of feeding as well. Autotrophic coral creates their own energy through a symbiotic relationship with algae while heterotrophic coral requires an external food source to derive energy from. This means the striking Tubastrea and Dendrophyllia coral may also be some of the best starter corals. Being some of the only Hermatrophic corals they are completely unaffected by light level and instead should be fed directly to maintain health. Many of my contemporaries cite this as a layer of difficulty but personally, I count accessibility to ease meaning that I recognize that the food and time to feed a "sun" coral may be easier than the $1,000.00 lighting purchase to keep autotrophic coral without any need to feed.
Regardless of the invertebrates, fish and coral you choose to start with the choices to come are many and you will soon grow to learn more about your tank and its inhabitants than you initially thought possible. Take time daily to observe your tank to address any issues as soon as they are noticed, but, primarily to enjoy the tank as much as possible.