Tom Obrecht's Reef Aquarium
When I first opened
the email asking me to be featured as Tank of the Month, I
thought it was a joke. Even though this is the biggest honor
I've had in all my years of keeping marine aquaria, I really
feel there are more deserving tanks out there. Nevertheless,
I have taken what I feel is a different approach from what
so many are doing nowadays, with small-polyped stony coral-dominated
tanks, and have instead focused primarily on an all soft coral
I started my aquarium hobby a bit
differently from most aquarists. In fact, I originally had
no interest in it at all. It began when my wife surprised
me with a small freshwater tank as a birthday gift. When asked
why she picked an aquarium for me, she replied, "Let's
go to the fish store and just pick some fish out and give
it a try." Little did either of us know the damage that
would be caused by this trip! Once in the store, the marine
fish on display instantly fascinated me. I dabbled in freshwater
fish for a couple of years, but I knew someday I would be
keeping a marine aquarium. From that small 15-gallon freshwater
tank, I quickly went to a 55-gallon tank followed by a 75-gallon,
a 180-gallon and my current 260-gallon tank. I'm now in my
10th year of keeping reef
My Current Aquarium:
My current aquarium is a custom-built
Oceanic tank that measures 60"L x 36"W x 28"H.
It has a powder-coated stainless steel frame that makes it
very nice not only for light penetration but also for working
in the tank. One 3" strip that runs down the tank's center
is the only brace. The tank has two 2" holes drilled
in the back glass for overflow drains. I have always preferred
this kind of overflow to the normal corner box for aesthetic
reasons and because it allows more real estate for livestock.
Other unique features of the system include two viewable sides
and a dedicated filter room in the basement.
Filtration and Circulation:
One feature I wanted when I planned
this tank was to keep all filter equipment in a separate location.
With my past tanks, I was always fighting the space constraints
under the main tank's cabinet. I really wanted to have the
ability to expand for more equipment as time went on, if the
The system's main filtration is a Deltec AP 902 protein skimmer.
I recently installed this unit mainly due to the tank's high
bioload. With my passion to keep adding one more fish, I felt
that the former skimmer I had was unable to adequately remove
enough organics. I couldn't be happier with this unit's performance.
Along with the skimmer I also have installed a My Reef Creation's
phosphate reactor. It usually contains about 500ml of phosphate
media, which I change every four to five weeks. Again, with
the number of fish and the amount of food I add daily, I felt
a bit of added security with this.
The main pump on the system is a Dolphin 4700, which takes
water from the lower basement sump and sends it upstairs through
three outlets into the main tank. With roughly 12' of head
pressure, I figure I'm receiving about 3000gph into the main
display. The three outlets are split between two 3/4"
Sea Swirl devices and another outlet positioned lower in the
back behind the rockwork to add more circulation in the lower
part of the tank. A large 1½" Swiss made check
valve is mounted directly above the main pump to prevent back-siphoning
in the event of an electrical outage. A 48"x 24"x18"
sump holds the skimmer, phosphate reactor and chiller coil.
I had the sump made at a local acrylic shop and even though
it's not fancy, it does the job at hand quite well.
A refugium was added about six months ago in the hopes of
adding a natural filtration method, as well as providing another
food source for the fish. The refugium measures 48"L
x 22"W x 16"H. One of the tank's 2" main overflow
drains goes directly into the refugium. After making its way
through the macroalgae, the water then drains into the sump,
is processed by the skimmer and is returned to the main tank.
Contrary to what many people believe,
this system requires a large amount of additives to stay healthy.
Much discussion has been written about the benefits of a calcium
reactor for stony coral-dominated tanks. Few have actually
realized its benefits on a soft coral-dominated tank. I installed
a Korallin 3002 calcium reactor about a year ago, and even
though it has benefited the system, I feel this unit is undersized
for the tank's demands. With the large numbers of soft corals
and their heavy growth patterns, I still need to add additional
calcium and magnesium in the form of kalkwasser, calcium chloride,
magnesium sulfate and magnesium chloride. I may need to purchase
a larger reactor in the future to better handle the load demands.
A ½ horsepower Aqua Logic chiller was initially installed
to keep temperatures in a safe zone, and the temperature now
typically stays in the 77 - 79°F range. A five-stage SpectraPure
RO/DI unit makes all top-off water for evaporation and water
changes. A GenX pump is also hooked into the tank via a closed-loop
system that's fed back into the main display through a third
¾" Sea Swirl. A Pinpoint pH monitor keeps track
of the daily pH range, which usually varies from 8.0 - 8.25.
Lighting consists of two 400-watt
10K Ushio metal halide bulbs powered by a Sunlight Supply
ballast. Supplemental lighting is provided by four 140-watt
VHO actinics. The combination of halides and VHOs really makes
the tank visually appealing and facilitates the corals' good
growth rate. All bulbs are changed on a 12-month rotation
to keep the light intensity from dropping off. The photoperiod
begins with the VHO actinics coming on roughly 30 minutes
prior to the halides at 1:00PM. The halides run for approximately
nine hours followed by 30 minutes of VHO actinics. The refugium's
lighting is on a reverse-daylight cycle from the main display
and has two power compacts as its light source.
My tank's parameters do fluctuate
from time to time. I feel this is attributed to the possibly
undersized equipment as the corals continue to grow. Weekly
testing helps keep parameters in check by allowing me to make
the needed adjustments. Levels are generally as seen in the
table to the right:
I rarely test for ammonia, nitrate or nitrite as the system
seems stable with regard to these parameters. All tests are
performed with Hach test kits.
My last 180-gallon aquarium housed
a wide variety of corals including large-polyped stony corals,
small-polyped stony corals, soft corals and clams. After several
bouts of trying to keep the small-polyped pieces happy, I
decided I would try an all-soft coral tank. I really like
the movement of the gorgonians, Xenia and star polyps
in the currents.
Current inhabitants include several large Sarcophytons
(one piece is almost 26" across), Sinularia, Anthelia,
Xenia, green star polyps, numerous mushrooms, clams,
Clavularia, gorgonians and anemones. I'm not really
into precise coral identification, but rather the coral's
shape and texture. Although the tank may not have the bright,
vibrant colors of a full-blown small-polyped stoney coral
tank, I feel the corals' shape and movement make up for it.
I'm not one to trim corals much; I like the thick, natural
The funny thing about the fish in
this system is that just a few years ago I was almost against
keeping fish in my reefs. Now, I'm approaching the 60 fish
mark! The main population of fish is Anthias species.
These fish simply fascinate me. They have tons of color, movement
and personality. Current Anthias species include: Pseudanthias
hutchi, P. squamipinnis (from various collection
locations), P. bicolor, P. bimaculatus, P.
caraberry, P. bartlettorum and P. pleurotaenia.
My favorite is the Pseudanthias bimaculatus. The male
is the boss of all the Anthias and both the male and
females have great coloration. Other fish include a yellow
tang, purple tang (both in my possession for over eight years),
Paracanthurus hepatus tang, maroon clown, copperband
butterfly, both green and blue Chromis and a large
rabbitfish. Feeding consists of a combination of frozen foods
- mysid, brine, bloodworms and daphnia, along with nori, which
is fed twice a day. Most people are really surprised with
the amount of food provided daily, but I feel with the number
of high-energy fish I have, this is right in line with their
Basic tank maintenance includes
top-off from evaporation with kalkwasser (roughly four
gallons per day) and additives as needed. Once per week
I perform a 25-gallon water change. This might seem
excessive, but with the large load of fish and the heavy
feedings, I feel it is something not to overlook. The
skimmer's cup is cleaned two to three times per week
to keep the skimmer performing optimally. Other than
that, the tank is pretty much self-sufficient.
What does the tank's future hold?
Well, in retrospect, I feel that a number of changes would
further enhance the tank's health. First is improving the
water flow. As the tank has filled in with corals, I can see
that I didn't plan accordingly in this area. I intend to enhance
water flow by installing another circular loop through the
back of the aquarium. The second change I think would be beneficial
is the openness of the rockwork. Even though I didn't overload
the tank with liverock, I still feel I could have done a better
job creating more open space through the reef's structure.
As time goes on I can see myself taking the tank down to thin
the fish population and trim back many of the corals. Last
of all, I feel the need for more space for some of the larger
coral pieces. Plans for a larger system are always rolling
through the back of my head. Little did I know 12 years ago
when looking into that 15-gallon tank that today the 260-gallon
would be packed full of marine life!
I'd like to thank some people who
made this system a success. First, thanks go to my wife for
tolerating all the times I've pushed the envelope for my hobby.
Many thanks to my friends and neighbors who have helped me
through difficult times and by "fish sitting" when
I am out of town. Last, but not least, I want to thank all
those from Reef Central and members of the Omaha
Marine Society for all their good advice through the years.
Some of my best friends have been made through this wonderful
Feel free to comment
or ask questions about my tank in the Tank of the Month thread
on Reef Central.
If you'd like
to nominate a tank for Tank of the Month, click here
or use the button to the right.