http://www.youtube.com/watch?v=lX542hTpg-U

The full EcoReef One tank from above.

The description of this tanks sounds like a list of things not to do when setting up a reef tank: it has no live rock, no live sand, minimal filtration, no additives, the water is never tested, 100% water changes and yet this 5 gallon glass box is one of the most attractive, successful and least demanding reef tanks that I have ever set up. It is not unusual for reefers to bend the rules once in a while but most reefers would never consider completely ignoring all of these pillars of modern reefing philosophy. You might think that there must be some kind of trick to this reefing heresy but as everyone who has been stunned by this tank can attest, this little nano reef fulfills all of the basic requirements of corals and it does so with very little material, energy or maintenance and a whole lot of style. Furthermore, the extremely efficient set up of this nano reef uses so little energy that it cost about a nickel a day in electricity consumption.

A little background

Photo 2. A look at this nano reef early in it’s setup when the ceramic reef was still new.

In the early 2000s, the reef aquarium discussion was heavily slanted towards recreating the entire ecology of the reef: you had to get a ton of live rock, a huge deep sand bed, lots of janitorial invertebrates for the clean up crew and a refugium to round out the parts of the ecosystem which didn’t jive with the main display. The more pods you had in your tank, the better off your reef would be because that is the way that natural reefs work. Although the majority of us were only trying to keep a nice group of corals and few reef fish in our home aquarium, suddenly it seemed like we were spending 80% of our time talking and focusing on rock, sand, crabs, shrimp, starfish, worms, amphipods, copepods, etc. Although there is nothing wrong with learning about the ecology of reef systems and being fascinated by the endless forms of invertebrate marine life, for too long many aquarist drifted away from the core needs of corals, the primary group of animals that most of us really want to keep and grow. With the idea of refocusing on corals in mind for my future reef tanks, I have been kicking around ideas for how to grow corals in an environment where the majority of the work goes directly towards benefiting my primary interest for keeping a reef tank, which is the thin veneer of living coral that we spend most of our time looking at.

Reefing Heresy: no live rock, no live sand

Photo 3. The barebottom of EcoReef One will one day be home to a living substrate of Diaseris pieces.

When I started in the reef aquarium hobby the pure Berlin method of reefkeeping was king and my reef aquarium philosophy is still strongly influenced by those early days of wider reef aquarium success. One of the main principles of the Berlin Method is to keep the aquarium clean. Mind you it was never advocated to keep the tank sterile like marine tanks of the eighties but having few fish, infrequent feedings and having a bare bottom was key to keeping the nutrients manageable with the limited equipment that was available back then. Ever since I have always hung on to barebottoms reef tanks and because of regular success with using bare bottom instead of any kind of sand, I have long been looking for a way to do the reefscape with a structure that would be the equivalent of a barebottom. Ceramic reef shapes have been available for over a decade but until recently these have been available only from Europe and the added cost of shipping from across the pond has made ceramic reefscapes very expensive. Recently a company out of Salt Lake City called CeramEco has been making extremely gnarly and ostentatious reef shaped ceramics that are much more affordable than their European made counterparts. I truly don’t have anything against live rock except that I feel that the porosity of the rock can be a drawback in the long term maintenance of a reef system. Gnarly live rock tends to accumulate detritus and nutrients over time, not to mention a large population of invertebrates which add to the bioload of the aquarium. By using ceramic reef structure that is very porous on the surface but not riddled with microcavities, I feel like there is still enough surface area for colonization by bacteria but now the nutrients that build up are in the water column or accumulating in predictable places where they can easily be removed from the system, not getting tangled up in the netherworld of live rock matrix.

Photo 4. A week after water change this little reef stays very clear through the use of a small amount of activated carbon.

Back to basics with very reduced filtration and activated carbon

I am all for having a pro-biotic environment but it is quite surprising how clean this tank stays when there is very little place for biofunk to accumulate. Since the majority of the biomass in this aquarium is coming from photosynthetic corals that are not purely heterotrophic, the diatom and filamentous algae growth is greatly reduced without any added snails or hermit crabs, just the stomatellas that hitched a ride in. Although there is some fleshy red macroalgae growth in this tank, it is periodically removed more for the shade they cause over corals than as a source of nutrient export. Aside from having an aquarium with ecology that is well balanced, a small Marineland Duetto mini internal filter serves triple duty as a mechanical filter, chemical filter and source of water motion in the EcoReef One nano reef. The Duetto has a small coarse sponge which traps large wastes and it holds one to two ounces of activated carbon which is replaced as needed to polish the aquarium water. In a tank this small a well directed flow nozzle can get all of the aquarium water moving without the need for additional water flow equipment. An adequate protein skimmer for this size of tank might hold 10-20% the volume of the tank and I find that using activated carbon is faster, more effective and a whole lot more discreet at removing dissolved organics than a puny inefficient protein skimmer.

Photo 5. 100% water changes are the norm for EcoReef One; it goes without saying that temperature and salinity are closely matched before the water change begins.

More Reefing Heresy: no dosing or testing and 100% water changes

One of the other reasons for the reduced filtration is that it is just so darn easy to do a large water change on this tank using a single bucket of water that it only takes ten minutes to “press the reset button”. The EcoReef One is scheduled to get a complete water change once a week but realistically this turns out to be 2-3 a month, and sometimes less when free time is scarce. Until very recently I never would have considered doing 100% water changes with the salts that were widely available but there is something special about the ESV B-Ionic Seawater. The 4 part system mixes up completely clear in about 10 minutes and when I first started using it I noticed that corals never show the type of short term irritation that we usually experience even when doing a partial water changes. Since mixed B-Ionic Seawater appeared to be so gentle on corals during water changes, one day I tried doing a complete water change with it and minutes after refilling the tank the corals showed no sloughing and there was none of the haziness commonly seen when doing a partial water change. Furthermore, ESV B-Ionic is such a complete salt mix that without any additional dosing I noticed all the corals and macroalgae developed very rich colors and the corals inflated their tissue to a puffyness as vigorous as any I’ve ever seen. Finally, the water change not only resets the nutrient levels but it also completely replenishes the mineral balance and trace elements of the aquarium. I could spend a lot of time trying to test and dose the tank but complete water changes all but negate the need to keep an eye on parameters besides temperature and salinity.

Photo 6. A balanced spectrum of LED spotlighting produces much richer colors than the 20K look.

A balanced spectrum of LED spotlighting

Aquarium corals can be very healthy under a wide range of conditions but without a well balanced light source to show off the corals, no one will ever be able to see it. What makes the lighting on this tank stand out is not just the LED technology that is producing the light but the balance between LED colors including cool white, warm white, standard blue and royal blue LEDs. The main light engine on EcoReef One is a 15 watt NanoCustoms 3:2 blue to white PAR38 LED spotlight. I started the spotlighting by using the newer 21 watt version of their light but I found that it was a little too bright. With the modest lighting demands of the LPS corals in this tank I was experiencing a little bit of bleaching in parts of the tank that had hotspots of light so I downgraded the power level by 6 watts. The lighting on EcoReef One includes two accessory LED spots including a three watt spotlight with blue LEDs that compliment the royal blue color of the 3:2 PAR38 lamp quite well, as well as a 3 watt warm white LED spot which is a “PAR Booster” light which I have programmed to come on for 4-6 hours during the middle of the day. Using the accessory spotlights is mostly to boost the color rendition of the overall LED spotlighting array but it also helps to spread the brightness in a way that is more practical than using a single spotlight.

Photo 7. This tank can still get the blue light fix by manually turning off all but the blue LED spotlight.

EcoReef One uses very little power

As if having a beautiful easy to maintain nano reef aquarium wasn’t enough, EcoReef One uses so little power that it may have already reached a lower limit for a tank like this. Here is the breakdown of equipment and power draw:

• Marineland Duetto- consumes 3-4 watts for the flow I have selected
• Marineland Mini shatterproof heater- rated for 10 watts but actually consumes 7 watts
• PAR 38 Spotlight – 15 watts
• Blue LED spotlight – 3 watts
• PAR Booster LED spotlight – 4 watts

Summary:

Photo 8. There is something about LED spotlighting that shows off a lot of detail on coral.

• Night time with filter and heater: 12 hrs @ 10 watts – 120 watt hrs
• Daytime with filter, heater and PAR 38 and blue spotlights: 8 hrs @ 28 watts – 224 watt hrs
• Daytime peak with all of the above plus PAR Booster spot: 4 hrs @ 32 watts – 128 watt hrs
• Total: 0.472 Kwh per day

Basically at $0.12 per Kwh in my area this tank costs $0.06 in electricity per day.

Some notes about this tank

What this tank doesn’t have much of yet is coralline algae. Since almost no live rock was used in the construction of this reef, coralline algae spores have had to hitch a ride on the limited real estate of the coral bases. I have added one dose of Coralline algae slurry harvested from other tanks and now I am beginning to see a few isolated spots of crustose coralline algae. One of the lessons learned while setting up this reef tank is that fresh ceramic structures leach silicates in significant amount. Had I known this in advance I would have soaked the ceramic to get rid of the silicate. Since I didn’t do this I was unpleasantly rewarded with diatom blooms which were sometimes so thick that I was almost discouraged by this live rock free reef system. The break in period was perhaps prolonged in this aquarium which began with very little biologically active surfaces but in time the aquarium system began to behave and respond like a typical reef system. One of the more interesting observations in this small volume aquarium is the supersaturation of oxygen after the PAR booster spot light has been on for a few hours. In freshwater planted tanks this is called “pearling” and the combination of many corals and the small biomass of red macroalgae in the small water volume increases the oxygen concentration high enough to form bubbles on the macroalgae. The formation of bubbles doesn’t seem to bother anything and it’s kind of neat to think the aquarium is high on oxygen for parts of the day.

Photo 8. Later in the day the oxygen reaches such a high concentration that there is pearling of oxygen bubbles.

EcoReef One is home to a cluster of Diaseris slices, “original” Duncanopsammia, five Scolymia australis, three Manicina areolata, one branching bubble coral, Plerogyra simplex, A couple of Echinophyllia and Acanthastrea species, a 5″ polyp of elegance coral with a 1″ skeleton and a pair of Harlequin shrimp, Hymenocera picta which are fed one arm of a chocolate chip starfish every 7-10 days.

Scaling up

Some aspects of this reduced-ecology reef aquarium scale up well to larger reef systems while some others will need modification. For example, the reef structure can easily be made of larger and larger ceramic reef structures, and the simple steampunk filtration can be made larger too. However the 100% water changes and lack of water testing that goes with it quickly becomes impractical and less economical on reef aquariums larger than about 20 gallons. For larger tanks partial water changes are more sensible and it will be necessary to test some chemistry parameters to learn how much the aquarium demands. Although the LED spotlighting works great for this small surface area with closely spaced corals, it would be inconvenient to have a huge array of spotlights on any tank longer than 3-4 feet. I currently have a 60 gallon version of this tank, EcoReef Two which will hopefully continue to push the limit of how little material or time is required to keep a reef aquarium and the corals looking good.

Photo 9. The rulers of EcoReef One, a pair of Harlequin Shrimp.

I want to thank the many people and businesses who have contributed to this project with equipment and livestock:

CeramEco donated the ceramic VidaRock which makes up the reefscape. NanoCustoms donated the PAR 38 LED spotlight that powers this reef. ESV sent along my first sample of B-Ionic Seawater for use on this reef, now I am hooked on it. CoralMorphologic threw in several beautiful Saint Thomas anemones, Discosoma sanctithomae. The Aquarium Showroom let me frag one of their show Acanthastrea bowerbanki and a beautiful melting pot style Echinophyllia chalice corals and many of the other frags are from reefing friends Gresham Hendee of Reef Nutrition, Kevin Kohen of LiveAquaria, Jason Edward of Greenwich Aquaria, Joe Yauillo of Atlantis Marine World and Chris Bueschelle of Reefkoi Corals. Thanks everyone!

http://www.youtube.com/watch?v=fhVNbj_Spvg

EcoReef One full tank from the sides

Photo 10. Between the tools that are used to run this nano reef and the extremely healthy corals the experiment that is EcoReef One has been very, very fulfilling.