Daniel Gan's (danano) Reef Aquarium
How It All Began:
I have always been fascinated by captive
aquatic life. For over 30 years, there has always been aquatic
life sharing my living space. Perhaps it was all inspired
by the small Koi pond at my parents' house that I used to
look after during my childhood. It was only after graduating
from UT Austin in 1991 and moving to Boston that I discovered
the world of marine fish and reefkeeping. I started out with
a 29-gallon acrylic tank and shortly thereafter, I setup a
10-gallon nano tank as well. In the early days, I kept mainly
fish, mushrooms, some hardy leather corals and zoanthids.
After moving to Southern California and back to Texas with
my two tanks, and then half-way around the globe with my 10-gallon,
I finally rooted myself here in Singapore. It wasn't long
before the upgrading process began. The 10-gallon tank soon
grew into a 30-gallon and today, a 110-gallon occupies a corner
in the living room.
The 110-gallon Tank:
The seeds for my 110-gallon were planted
in May 2004 and by July, all the corals and live rock from
the smaller tanks were transferred to this tank. I created
a semi-deep sand bed, sloping from 4" at the rear to
about 2 - 3" in front. Biological filtration is provided
by 130 lbs. of premium cured live rock. T5 lighting with quality
mirror finish reflectors provide edge-to-edge illumination
for the light loving corals and clams. A Barr Aquatics SK1600
Beckett-injected skimmer, carbon and Rowaphos keep the water
crystal clear. Besides a few clams and LPS coral in the lower
third of the tank, the reef slopes in the tank depict dense
I also keep several pygmy angels that get along well and,
so far, have been good reef citizens.
There were two primary considerations when designing the
tank. First, I wanted to be able to see the true colors of
the reef through the glass. I decided, therefore, on starphire
glass for the front and right viewing panels. The second consideration
was to maximize the useable space in the tank, and this meant
the overflow box would have to be external.
With ambient temperatures seldom dropping below 76º
F and reaching as high as 86º F on hot afternoons, heat
is an issue. Fortunately, advances in high output T5 technology
have provided a viable alternative to metal halide lighting
with less heat generated. Using T5 bulbs allowed me to design
a much sleeker hood standing a mere 6" high. The cabinet
has louvered doors and is without any side or rear panel for
maximum ventilation. The dark walnut finish blends in well
with the rest of the living room furniture.
110-gallon tank with starphire viewing panels,
black backing and external overflow box
display tank dimensions are: 48" L
x 24" W x 22" H (overflow box
6" x 16" x 14")
sump/refugium: 36" x 18" x 16"
holding/propagation tank: 29" x 15"
Filtration, Circulation & Chiller:
A 40-gallon sump sits in the cabinet partially extending
out to the left below the overflow box. One Eheim 1260 external
pump (2,400 L/hr) draws water from the sump, passes the water
through a 1/3 HP Daeil chiller (Artica OEM) before ultimately
returning it to the tank. Another Eheim, a 1262 (3,400 L/hr),
serves purely as a return pump. Both pumps are run externally
so as not to introduce unnecessary heat into the system. A
Resun MD55 drives water into the Barr Aquatics SK1600 Beckett
I chose to go with a powerful skimmer
rated for a total water volume of up to 500 gallons to allow
greater flexibility as far as stocking and future system /
I use about 130 lbs. of premium Fiji and Vanuatu live rock
for biofiltration. Approximately 120 lbs. of fine grade 0
sand form the semi-Deep Sand Bed, starting out at 4"
at the rear sloping down to 3" in front. Chemical filtration,
consisting of Rowaphos and Seachem Matrix Carbon in filter
bags, are placed in a high flow area in the sump and help
to keep the water crystal clear.
In addition to the two Eheim returns, I run two 6000 streams
with a Tunze 7094 Multicontroller. Three Maxijet 1200 powerheads
assist in minimizing dead spots. The combined maximum flow
rate of almost 23,400 liters per hour translates to a maximum
turnover of about 56 times, keeping the SPS happy.
In our hot climate, and given the highly delicate nature
of SPS corals, heat is an obvious major concern. A chiller
and/or chiller-pump failure would be disastrous. Within a
few hours, a temperature rise of a more than 8º F would
be highly detrimental, especially to the SPS. Compared to
the time, effort and resources put into acquiring and maintaining
the tank inhabitants, the cost of adding a redundant chiller
would appear insignificant. Hence, it was not a difficult
decision for me to add a 1/4hp Daeil chiller to give me the
piece of mind. The chiller is connected to an Eheim 1250 pump
that feeds the 25-gallon propagation/holding tank which returns
to the sump. As an added precaution, I also have a Fox Controller
that I plan to install that will automatically switch the
lights off in the event the temperature goes above 84º
As I embarked on creating the reefscape, my aim was to simulate
a densely packed hard coral (mainly SPS) garden and at the
same time, provide a 'natural' environment for the fish to
hide and swim in containing numerous crevices and caverns.
Large staghorn type live rock and a few large pieces of live
rock form the base of the main reef structure, allowing pillars
and spacious caverns to be created beneath the reef slopes,
while also providing a refuge for the fish and other reef
dwellers. I also used medium-size and flattish live rock to
allow greater reefscaping options. Parts of the reef structure
consist of Porites rocks that were the foundation for my earlier
two tanks. Porites encrust fairly quickly and they fuse together
within a few months, resulting in a very stable structure.
The two Tunze streams drop into small slots I created at
the top-rear within the reef structure to ensure an unobstructed
view. However, being partially hidden behind the live rock,
the flow is compromised somewhat, which is why I am considering
adding another Tunze stream to optimize water flow in the
Calcium & Alkalinity Supplementation:
In order to keep up with the uptake of calcium, I use a
DIY modular system dual chamber calcium reactor with about
30lbs. of CaribSea ARM media in the first chamber and another
10lbs. in the second chamber. I started out with a single
reaction chamber, and it wasn't long before I added a second
chamber in order to keep up with the calcium demands of the
Holding/propagation tank & equipment.
After getting good results with T5 bulbs in my previous 30-gallon
system, they were the natural choice for my current 110-gallon
setup. While the 24-watt T5s did a decent job maintaining
SPS color at shallower depths, I was pleasantly surprised
to discover that the 54-watt versions allowed me to maintain
SPS even on the sandbed.
Top view of the T5 reflectors.
I started out with six 54-watt T5s, but it wasn't long before
I increased the lighting to eight 54-watt T5s with the addition
of more light demanding corals. The bulb combination now consists
of five ATI Aquablue Special (11,000K) and three ATI Blue
Plus (Radium equivalent) for maximum intensity and yet still
provides a balanced spectrum for coral growth and color.
After using T5 bulbs for over two years, and almost nine
months in my current tank, I must say that I am very pleased
with the results in terms of coral growth and color. Aside
from quality T5 tubes, equally important are the mirror finish
ATI parabolic reflectors that rest directly on the tubes for
maximum reflectivity. One of the keys to getting good results
with T5 bulbs, I believe, is to keep your SPS no more than
18" from the light source. For intensely colored SPS
(i.e. reds, blues, pinks, neon yellows), I keep them less
than 10" away. The T5 bulbs are no more than three inches
from the water surface. Three 24-watt T5 bulbs light up the
refugium and another six 24-watt T5 bulbs cover the propagation
The main tank is on an 11 hour photoperiod, from 12:30pm
to 11:30pm. The sump-refugium is on a 10 hour partial reverse
photoperiod, from 3:30am to 1:30pm. The propagation tank is
also on a 10 hour partial reverse photoperiod from 7:30am
to 5:30pm. This helps to maintain the pH above 8.00 after
the main tank lights go out.
Maintenance & Husbandry:
I perform a 5-10 percent water change weekly using Tropic
Marin salt mixed with oxygenated distilled water. Detritus
build-up is siphoned once a month. The skimmer collection
cup is cleaned bi-weekly. In addition, the tank viewing panels
are cleaned every three days using a pair of algae-cleaning
magnets. I trim the macroalgae in the refugium once a month.
Bi-weekly water tests are conducted with Salifert Ca and dKH
test kits. With the tank now mature and stable, other tests
are performed on rare occasions. Nitrate, nitrite and phosphate
levels are undetectable. As a result of exclusively using
distilled water, the alkalinity tends to be lower. Therefore,
I occasionally mix Reef Builder with top-off water to raise
the dKH when needed. I feel that frequent water changes are
essential as a means for nutrient export and trace element
replenishment to maintain a healthy captive reef environment.
SPS pruning is also a routine maintenance exercise but many
times, I let nature take its course with the stronger species
prevailing. More often than not, the chemical warfare ends
in a tie or they just grow away from each other or stop growing
altogether at the point of contact.
The reefscape was constructed with predominately SPS and
a few fish in mind. That said, over 80 species of SPS corals
now blanket the reef slopes and walls with assorted Montipora
capricornis occupying the lower half. The multiple swim-through
caverns provide a safe haven for the fish with ample quality
live rock for their grazing.
With a densely packed SPS dominated tank, chemical warfare
is expected. I simply let the corals fight it out, although
I do prune certain fast growing corals on occasion.
SPS: over 80 species, including various Acropora,
Montipora, Millepora, Seriatopora, Stylophora, Pocillopora
LPS: assorted Blastomussa, Acanthastrea, Echinophyllia,
yellow Turbinaria, red-green Lobophyllia.
Clams: Tridacna maxima, T. crocea.
Fish: Flame angel, Potter's angel, Multicolor
angel, Cherub angel, Purple tang, Yellow-eye Kole tang,
3 Orchid dottybacks, Mandarin goby, yellow Canary wrasse,
green Leopard wrasse, black Leopard wrasse, Yellow-fin
wrasse, Possum wrasse, 2 Green chromis, orange Skunk clown.
Invertebrates: 2 Sally lightfoot crabs, 2 Cleaner
shrimp, Coco worm, Nassarius snails, Bumble bee
snails, Acropora crabs.
I find that certain fish continuously pick on the live rock
and bases or undersides of corals. This includes pygmy angels,
tangs, some wrasses and dottybacks. The right mix and number
of fish in a reef tank has its benefits. I think they help
maintain an eco-balanced system by not allowing parasites
to take hold in a captive environment by keeping them in check
and preventing them from infesting corals. These fishes peck
on anything that moves on the rocks and I think this reduces
the parasite's potential to reproduce. Similarly, I believe
Acropora crabs play an equally important function as
guardians of their SPS homes.
Like many, I was initially weary of adding a pygmy angel
into my tank, let alone four of them. After much research
and reading on the experiences of others, I successfully kept
a Cherub in my old 30-gallon, which I later transferred to
the current tank. Angels add a lot of life and color to a
reef tank and naturally, I took the leap of faith, gradually
adding three more pygmies! I added a medium-sized Potter's
and a Multicolor at the same time. A few weeks later, a small
Flame angel joined the threesome. The tiny Cherub was overtly
territorial and chased the larger fish initially, giving up
after only a day or two. The angels stay fat from simply grazing
the live rock, and they all take Formula 1 & 2 except
for the Potter's. They take an occasional rare nip at an SPS
polyp or two, nothing more.
The Orchid dottybacks, Cleaner shrimp, Sally lightfoot and
acro crabs have all spawned in the tank. In every instance
that I've witnessed, it occurred about an hour after lights
Feeding and Supplements:
I feed the fish Formula 1 & 2 pellets every two to three
days. For general consumption, I feed a stew of Liquid Life
Bioplankton, finely chopped nori, Cyclop-Eeze® and Formula
1 flake once a week.
The angels, tangs, mandarins and wrasses are self-sustaining.
They graze and peck on the live rock the whole day. The orchids,
clown, chromis and yellow fin wrasse require supplemental
I dose iodine and amino acids for potential benefits to the
corals. I have noticed what I believe to be slightly improved
coloration and polyp extension with the addition of amino
About a week ago, I made an amazing discovery! What I found
was a natural offspring of one of the SPS corals in my tank.
I noticed a small growth, encrusting on the top edge of the
overflow glass leading to the last compartment in the sump.
The encrusting growth is about the size of a small coin with
tiny bumps/branches/polyps beginning to form. On closer inspection,
the mother colony is likely the purple or pink Pocillopora
sp. in the main tank. There are two other smaller encrusting
spots along the same glass edge. T5 bulbs light up the sump/refugium
on a reverse photoperiod, providing indirect light to the
last compartment and it's apparently enough light for the
new SPS growth. Needless to say, I was very excited about
the new find, and I am still amazed! I estimate that the baby
colonies are probably no more than six to eight weeks old.
I would not have made it this far without the support and
understanding from my loving wife. In fact, on one occasion,
she picked out, with her trained and discerning eye, the purple
A. humilis that now sits smack at the highest point
of the tank. Together, we enjoy our small piece of the ocean
in the living room and never seem to get bored staring into
it, always amazed and discovering something new each time!
It's a special joy to see the corals grow and color up. And
it's an equal joy to see the fish swimming among the corals
and crevices and greet us when we are near. And it's the continuous
challenge plus learning and sharing of experiences that makes
this hobby and passion of ours so enjoyable and addictive!
Most of all, a special appreciation goes out to Reef Central
and a big, "Thank you!" to Reefkeeping Magazine
for the excellent articles and tank features, which have been
an invaluable source of information and inspiration for me!
I would like to add that I am truly honored to be given this
opportunity to share with you our small piece of the ocean!
**All photos copyright Daniel Gan.**
Feel free to comment or
ask questions about my tank in the Tank of the Month thread
on Reef Central.