D
1
CORALZOO
3.3. Displaying corals - general guidelines
Tim Wijgerde
As discussed in paragraph 3.1, rearing and displaying corals are two separate principles.
Whereas growth rates and morphology are key aspects of rearing corals, displaying these
invertebrates is all about practical system design, aesthetics and natural appearance.
System design
Many zoos and public aquaria nowadays take great effort in designing public displays. The
current trend is to naturally incorporate the vivarium, the space which contains the organisms
on display, into the rest of the building. For an aquarium, this can be done by constructing a
natural-looking framework such as artificial rock, over the aquarium's edges. Designs should
be constructed in such a way that it does not interfere with daily routines, such as window
cleaning and equipment maintenance. Designing a public display should therefore always
include feedback from zoo staff during the entire process, including aquarists and supporting
staff such as janitors, to ensure its practical nature. In other words, the design and
construction of a given aquarium display should follow the principle of practical before pretty.
For maintaining a stable environment (system homeostasis) to ensure healthy corals and
fish, advanced equipment should be installed. Several important (water) parameters have to
be monitored and controlled carefully. Although the importance of these parameters are
discussed in paragraphs 3.2.1, 3.4.1, 3.6.1 and 3.8.1, the equipment required for maintaining
these will be discussed below.
- temperature
A thermostat, in combination with adequate heating capacity, should be installed. Heating
capacity depends on several physical aspects, such as system volume, aquarium and
building isolation, climatic properties of the aquarium's location (e.g. (sub)tropical or
temperate) and desired optimal temperature. For smaller displays, in the range of 100 L 10,000 L, common aquarium heaters and aquarium chillers with heating function will suffice.
It must be noted that most systems only require cooling, as lighting and other equipment
generate ample heat.
The same principles apply to cooling the aquarium; ample capacity is required, depending on
aquarium characteristics and desired temperature. A heat reclaiming system, where excess
heat is stored in subterranean spaces for later use, is of great value for saving energy.
Excessive heat emanating from aquarium lamps, pumps and coolers may be used during the
winter. These systems are now becoming widespread in public buildings.
- pH
The acidity, or pH (negative logarithm of hydrogen ions, H+), is an important chemical
parameter of seawater. In general, seawater has a pH which lies around 8.2. Due to the
buffered nature of seawater (mainly caused by (bi)carbonate ions and sheer volume), this
September 2009
D
2
CORALZOO
value does not significantly fluctuate in open marine water bodies such as coral reefs. In
aquaria, pH has a tendency to fluctuate. This is usually caused by the high ratio between
biomass and water volume. Nocturnal respiration of animals, plants and bacteria leads to a
buildup of CO2, thereby decreasing pH. Preventing this value from falling too low is
important, as low pH levels have negative effects on the aquarium's inhabitants. As a general
guideline, a pH between 8.2 during the day and 7.8 or higher during the night is
recommended. This can be obtained by sufficient aeration of the aquarium water, by means
of protein skimming and air pumps, and by not overstocking the aquarium. Another option is
attaching a second system with inversed photoperiod onto the primary system. This auxiliary
tank should be stocked with photosynthesizing biomass, such as Chaetomorpha
macroalgae. This will ensure CO2-uptake and stable pH during a 24-hour period. For large
systems, containing ample fish and coral, large auxiliary systems will also be required.
pH probes should be installed on any aquarium, preferably connected to a computer logging
system. This allows for monitoring overall system health and performance.
- dissolved oxygen
Closely linked to pH is dissolved oxygen, or DO. Higher aeration levels will lead to more CO2
outgassing, and therefore higher pH levels. A recommended value for DO is between 8 -10
mg/l (87 - 110% saturation) (Buentello et al., 2000; Foss et al., 2003). These values can be
obtained by strong aeration of tank water by means of protein skimmers, air pumps, overflow
systems and sufficient surface water movement.
- lighting
Aquarium lighting is a key parameter for maintaining live corals. When considering different
light sources, aquarium dimensions are important, as well as lighting requirements for tank
inhabitants. Tanks with greater depths require more lighting power.
Most public aquaria have fairly large dimensions, including depth. This last dimension may
be the decisive factor for choosing optimal bulb type. Tanks intended to house stony corals,
with vertical depths of 75 cm and above, should have metal halides (also referred to as HQI,
or Hydrargyrum quartz iodide) installed. Only these light sources carry sufficient capacity to
reach the entire depth of the display, ensuring ample light reaches the corals. Soft corals and
gorgonians seem to require less irradiance compared to most stony corals as the latter group
is highly dependent on light for optimal calcification rates (Falkowsky et al., 1984; Gattuso et
al., 1999; Schutter et al., 2008 and references therein). As a rule of thumb, a minimum
irradiance of 100 μE/m2/s should be applied for zooxanthellate (containing symbiotic algae,
requiring light for photosynthesis) corals and gorgonians (Schutter et al., 2008). High
irradiance also stimulates endogenous coral pigmentation and decreases zooxanthellae
pigmentation, which yields colourful corals (Riddle, 2009 and references therein). This last
aspect may be important when regarding coral appearance in public displays.
Fluorescent lighting, such as T8, T5 and PL bulbs, and LED's may be supplemented to metal
halide lighting. These lamps are available in a wide range of colours, of which blue (e.g.
Osram colour 67) serves several purposes. First, supplementing yellowish metal halides with
September 2009
D
3
CORALZOO
blue lighting has aesthetic advantages, stimulating natural fluorescence in coral tissue.
Corals produce a wide array of pigments, of which GFP's (green fluorescent pigments) are
aesthetically pleasing (Riddle, 2009 and references therein). Second, bluish light is a natural
condition in waters over five meters in depth (Joshi, 2005), where the red part of the light
spectrum is increasingly attenuated by the water. Species which inhabit deeper waters
should be displayed under such conditions. Finally, combining blue lighting with a natural
moonlight cycle may stimulate reproductive behaviour in fish and corals (Levy et al., 2007).
Figure 1. Aquarium lighting is a key
parameter for maintaining live corals. This
system - in Tierpark Hagenbeck, Hamburg,
Germany - utilizes both metal halide and
blue fluorescent lighting. The blue lighting
gives the tank a bluish appearance, which
is aesthetically pleasing. It may additionally
serve to mimic natural moon cycles, which
may stimulate reproductive behaviour of
tank
inhabitants
such
as
corals
(photograph: Tim Wijgerde).
- water movement
Water movement is essential for most coral reef inhabitants, including fish and corals. High
water flow carries vital nutrients to coral tissue, removes excess mucus and waste products
such as ammonium, and stimulates gas exchange (see paragraph 3.6.1 and references
therein). Water flow levels of 10 cm/s and higher have been shown to stimulate coral growth
(Schutter et al., 2009, in preparation).
To obtain high water flow, especially in large systems, powerful equipment is required. For
small displays of up to 10,000L, submersible propeller pumps designed for the hobby
industry will suffice (pers. obs.). These have capacities of up to 30,000 liters/hour. For larger
displays, powerful turbine pumps are required. Various models from different manufacturers
are available; operating costs are a key factor here.
- nutrient removal and automated addition of supplements
Maintaining low nutrient levels is highly important, as high nitrate and phosphate levels will
lead to excessive algae growth in well-lit systems. Furthermore, there is increasing evidence
high phosphate levels ( > 0.1 mg/l or 1 μM) interfere with the process of calcification in
marine organisms (Kinsey and Davies, 1979; Björk et al., 1995). Using powerful protein
skimmers, in combination with live rock as biofiltration (in which both nitrification and
denitrification processes take place) has yielded good results in many aquaria (Delbeek &
Sprung, 2005).
September 2009
D
4
CORALZOO
Adding supplements may be performed manually, however it is highly recommended that
part of this process is automated. For adding macro elements such as calcium and
bicarbonates essential for coral growth, a calcium reactor is highly recommended.
Fig. 2. A calcium reactor. Tierpark Hagenbeck, Hamburg, Germany
(Photograph: Tim Wijgerde).
As a guideline, the reactor volume should be up to 10% of the total
system's volume (Walter Dorriné, pers. comm.). As most calcium
reactors do not nearly carry sufficient capacity to supplement a
large aquarium with macro elements, manual addition is often
performed as well. This method is commonly referred to as the
Balling method (Balling et al., 2008, and references therein, also
see paragraph 3.8 for more details about water quality).
- reliable equipment
For most of the above parameters, computer systems may be installed which are connected
to the appropriate probes. This allows for real-time monitoring and logging of essential
aquarium parameters. Such equipment is ideal for retracing system faults, which may be
linked to accidental loss of animals. Furthermore, a computer system which monitors and
controls aquarium equipment also facilitates aquarium maintenance.
Figure 3. A computer system which monitors
parameters and controls equipment greatly
aquarium maintenance and monitoring
performance - Tierpark Hagenbeck, Hamburg,
(photograph: Tim Wijgerde,).
aquarium
facilitates
aquarium
Germany
System stocking and aquascaping
When stocking the system with biomass, the biotope of choice determines what species
should be introduced. Similarly, landscaping the aquarium with (live) rock should be adjusted
accordingly. Even when only coral biotopes are considered for aquarium design, ample
choices remain. One can distinguish between reef fronts, flats and slopes on fringing and
barrier reefs exposed to waves, tranquil lagoons , seagrass beds, mangrove forests, river
September 2009
D
5
CORALZOO
estuaries and caves. All these biotopes may harbour corals, although large differences in
irradiance, photoperiod, water quality, current, salinity, temperature and sedimentation may
exist. These abiotic factors have shaped the biodiversity in these areas, which should be
mimicked accordingly in a public display. When respecting the physico-chemical parameters
corals and other marine organisms are exposed to in a given biotope, as well as the
biodiversity (or lack thereof), this will contribute to a healthy and natural-looking system.
- open fringing and barrier reefs
Open reefs are exposed to strong tides and heavy wave action. At such sites, coral species
occur which produce thick, compact skeletons resilient to physical disturbances. These reefs
often have steep drop-offs, which may be nicely mimicked in a public aquarium. Species
which are abundant here are mostly Acropora spp., Montipora spp. Seriatopora spp. and
Porites spp., although reef slopes may display very high biodiversity (for a detailed list of
families, genera and species see Veron, 2000). Steep drop-offs should be built in aquaria
with ample horizontal depth only, to allow access for maintenance and cleaning.
- lagoons
Lagoons are created by both fringing and atoll reefs, and often contain species resilient to
sedimentation and environmental extremes such as high salinity and temperature (Veron,
2000). These biotopes do not receive ample current, but are often subject to high variation in
water levels due to tide action. Genera occurring here often have species with delicate, large
polyps, such as Catalaphyllia jardinei, Favia spp., Oulophyllia spp., Lobophyllia spp., Fungia
spp. and Heliofungia actiniformis (Veron, 2000).
- sand bottoms
Sand bottoms form distinct biotopes which often harbour corals, albeit in low diversity and
number (Fisk, 1983). These areas are characterized by low light levels due to increased
depth (> 30 m), high turbidity, high sedimentation and the absence of coral reefs (Fisk, 1983;
Veron, 2000). These areas usually occur in between islands. Species found here are often
scattered across the ocean floor, and include large-polyped species such as Catalaphyllia
jardinei, Euphyllia spp., Trachyphyllia geoffroyi, and Fungiid corals such as Cycloseris spp.
and Diaseris spp. (Borneman, 2002; Fisk, 1983).
- seagrass beds
Seagrass beds are unique biotopes which often harbour corals, albeit in low diversity and
number (Fisk, 1983). These areas are characterised by low light levels due to shading of
seagrasses such as Cymodocea spp. and Halodula spp., high turbidity, high sedimentation
and the absence of reefs (Coles et al., 2004; Fisk, 1983).
Coral specimens found in sea grass beds are most often Catalaphyllia jardinei, which are
dispersed as solitary colonies (Borneman, 2002; Fisk, 1983). Although not a popular biotope,
a display containing sea grasses with Catalaphyllia jardinei colonies would be fascinating,
educating the public about the variety of coral habitats.
September 2009
D
6
CORALZOO
- mangrove forests
Mangrove forests are intricately linked to coral reefs, as these biotopes are home grounds for
many juvenile coral fish (Mumby et al., 2004; Robertson and Duke, 1990). Although coral
cover usually is sparse in these eutrophic and turbid waters, many fish dwell in between
mangrove roots. Setting up such a display therefore provides a stunning view into this rather
unfamiliar biotope. Several species of corals will handle a more nutrient-rich and shaded
environment, such as Xenia spp. and Catalaphyllia jardinei (Borneman, 2002; pers. obs).
When adding a variety of juvenile angelfish, surgeon fish, wrasses, filefish and parrot fish,
this provides a colourful display. Sponges often do well here as well, feeding on the ample
dissolved and particulate nutrients (Diaz et al., 2004). When stocking the system, using small
trees and planting seedlings will allow for natural development of the system. Most species
grow slowly at high salinities (Ball and Pidsley, 1995), hence supplementing the system with
artificial root systems made from polystyrene or epoxy is recommended.
- river estuaries
River estuaries may harbour sand beds, seagrass beds and even coral reefs. These areas
are subject to increased sedimentation, eutrophication and salinity fluctuations (Pritchard,
1967). Although many coral species have adapted to these unfavourable conditions, species
diversity and coral growth may be reduced. As such areas may harbour significantly less
coral species compared to other biotopes discussed in this paragraph, mimicking such a
habitat may be interesting in light of
education.
- coral caves and overhangs
Figure 4. An artificial overhang,
constructed around the Underwater
Marine Observatory in Eilat, Israel.
Such displays provide a unique
insight into these subhabitats when
decorated with various species of
soft
coral
and
gorgonians
(photograph: Tim Wijgerde).
Geological processes such as
tectonics and erosion have formed caves, which also occur in many coral reefs. Such poorly
lit subhabitats are often home to countless species of sponges, but also ahermatypic corals
such as Dendronephthya sp., Scleronephthya spp., Tubastrea spp., and many gorgonian
species. These animals do not require sunlight, as they are all azooxanthellate, and therefore
grow well at such sites as competition with algae and stony corals is absent.
Mimicking such caves and overhangs by means of creative aquascaping provides a stunning
view of this unseen world, and will captivate visitors. These corals will require heavy feeding,
which makes maintaining these displays labour intensive. Using "plankton-friendly" nutrient
removal systems (denitrifying bioreactors with auto- or heterotrophic anaerobic bacteria,
September 2009
D
7
CORALZOO
deep sand bed systems such as Dymico1 and algae filters) is recommended, to ensure
continuous high concentrations of phyto-, zoo and bacterioplankton, and detritus. Setting up
such a display disconnected from other aquaria is recommended, as these could otherwise
be plagued by excessive growth of benthic algae. It must be mentioned here that there is
very little success in keeping species such as Dendronepthea sp. alive long term in captivity
- coral orientation
A great variety in coral morphology exists, such as plate-like, encrusting, massive and
branching (Veron, 2000). These growth forms reflect the abiotic factors such species are
exposed to. In this respect, light and water flow are most important (Kaandorp et al., 2005),
and these should be properly mimicked (see paragraphs 3.2.1, 3.4.1 and 3.6.1).
Colonies with small polyps (this includes all known morphologies), such as Acropora spp.,
Montipora spp., Stylophora spp., Seriatopora spp. and Porites spp. are generally exposed to
high flow in nature (Veron, 2000). These species should therefore be placed at exposed
areas in the aquarium, well within the reach of powerful flow pumps. They may be glued onto
(live) rock with epoxy resins, or stuck into crevices.
Massive colonies with large polyps, such as Lobophyllia spp., Symphyllia spp., Euphyllia
ancora, submassive colonies such as Goniopora spp., Alveopora spp. and Euphyllia spp.,
and solitary polyps such as Trachyphyllia geoffroyi do not thrive well when exposed to very
high direct currents (pers. obs.) They may be placed at exposed areas, however not directly
in front of the output from pumps as this damages the delicate tissue (pers. obs.).
Ahermatypic or zooxanthellate corals, such as Dendronephthya sp., Scleronephthya spp.,
and Tubastrea spp., should be placed in dark areas to prevent fouling by algae. Placing them
in caves and overhangs with epoxy resin also provides a natural appearance to the display.
- species diversity and colony size
Some public aquaria, and this holds especially true for home aquaria, suffer from the
keeper's prolific nature to collect many species. This often leads to aquaria displaying many
small colonies, of many species. Although appealing as this may sometimes be, it is rather
unnatural. Most reefs are dominated by relatively few species, which may cover areas for
hundreds of meters in length (Veron, 2000). Of course, aesthetics is always important when
dealing with public displays, hence finding the middle ground is important. Reef slopes
contain highest species diversity, including plate-like, encrusting, massive and branching
corals (Veron, 2000). When coral reef displays are supplemented with aquaria showing sand
beds or seagrasses, it still allows for presenting a wide array of coral species to the public,
without conflicting with realism.
- aquascaping
As mentioned earlier, the biotope of choice largely determines the aquascaping of any coral
display. Rocky reef slopes have a different topography compared to lagoons , sand bottoms
or seagrass beds, which contain little rock but rather sediment. Most coral displays, both at
September 2009
D
8
CORALZOO
home and in zoos and public aquaria, mimic reef slopes. These rock walls allow for the
placement of many corals, however they are becoming rather mundane. Creating large
caves, overhangs and sand bottoms with little rock provides an interesting variation to the
array of coral displays.
The usage of ample rocky substrate is tempting, however this could pose long-term problems
as less room is available for coral growth. By making use of less substrate, and less
colonies, more room for colony expansion is allowed. In this sense, less is more.
Concluding remarks
In conclusion, when designing any coral system, three key issues should be respected:
- practical aspects such as easy maintenance (practical before pretty) and monitoring (
such as probes with logging and control computers)
- simulation of physical and chemical parameters, such as (high) irradiance and low
nutrient levels
- respecting the topography and species occurrence/diversity of the biotope to be
displayed
When these issues are addressed appropriately, highly realistic and well-functioning public
coral displays may be realised as a result. For more information on system design, life
support systems and stocking, the reader is referred to Leewis and Janse (2008).
Note:
1. Dymico, Dynamic Mineral Control, is a fairly new filtration system which utilizes
heterotrophic anaerobic bacteria for removing inorganic nitrogen. Carbon (e.g. acetate) is
actively pumped into the substrate to ensure high denitrification levels. Redox and pH probes
monitor the biochemical processes occurring in the sand bed, allowing for optimal regulation
of the process. Membrane pumps actively circulate the water through the sand bed,
delivering nitrate-rich water to the hypoxic layer for subsequent conversion into nitrogen gas
and carbon dioxide.
References:
Ball, M.C. and S.M. Pidsley, 1995. Growth responses to salinity in relation to distribution of
two mangrove species, Sonneratia alba and S. lanceolata, in northern Australia, Functional
Ecology 9:77-85.
Balling, H.-W., M. Janse, and P.J. Sondervan, 2008. Trace elements, functions and
replenishment in reef aquaria. Chapter 15 in: Leewis, R.J. and M. Janse (eds.), 2008.
Advances in Coral Husbandry in Public Aquariums, Public Aquarium Husbandry Series, vol.
2., Burgers' Zoo, Arnhem, The Netherlands: 143-156.
September 2009
D
9
CORALZOO
Björk, M., S.M. Mohammed, M. Björklund, and A. Semesi, 1995. Coralline algae, important
coral-reef builders threatened by pollution, Ambio 24: 502-505.
Borneman, E.H., 2002. Do You Know Where Your Corals Are Coming From?
Ecological Information for Aquarists from Coral Collection Areas in Indonesia - Part II,
Advanced Aquarist's Online Magazine 3.
Buentello, J.A., D.M. Gatlin III and W.H. Neill, 2000. Effects of water temperature and
dissolved oxygen on daily feed consumption, feed utilization and growth of channel catfish
(Ictalurus punctatus). Aquaculture 182: 339-352
Coles, R., L. McKenzie, S. Campbell, J. Mellors, M. Waycott, and L. Goggin, 2004.
Seagrasses in Queensland waters - current state of knowledge, CRC Reef Research Centre,
Ltd.
Delbeek, J.C. and J. Sprung, 2005. The Reef Aquarium, Volume 3: Science Art and
Technology. Ricordea Publishing, Coconut Grove, USA: pp 680
Diaz, M.C., K.P. Smith, and K. Rützler, 2004. Sponge species richness and abundance as
indicators of mangrove epibenthic community health. Atoll research bulletin, National
Museum of Natural History, Smithsonian Institution, Washington, D.C., USA, no. 518.
Falkowski, P.G., Z. Dubinsky, L. Muscatine, and J.W. Porter, 1984. Light and the
Bioenergetics of a Symbiotic Coral. Bioscience 11: 705–709.
Fisk, D.A., 1983. Free-living corals: distributions according to plant cover, sediments,
hydrodynamics, depth and biological factors. Marine Biology 74: 287-294.
Foss, A., T. Vollen and V. Øiestad, 2003. Growth and oxygen consumption in normal and O2
supersaturated water, and interactive effects of O2 saturation and ammonia on growth in
spotted wolffish (Anarhichas minor Olafsen). Aquaculture 224: 105-116
Gattuso, J.P., D. Allemand, and M. Frankignoulle, 1999. Photosynthesis and calcification at
cellular, organismal and community levels in coral reefs: a review on interactions and control
by carbonate chemistry. Am. Zool. 1: 160–183.
Joshi, S., 2005. Spectral analysis of 250W double ended 10,000K metal halide lamps and
ballasts: EVC, Happy Reefing, IceCap, AB, and Coralvue. Advanced Aquarist's Online
Magazine 4.
Kaandorp, J.A., P.M.A. Sloot, R.M.H. Merks, R.P.M. Bak, M.J.A. Vermeij, and C. Maier,
2005. Morphogenesis of the branching reef coral Madracis mirabilis. Proc. Roy. Soc. B. 272:
127-133.
Kinsey, D.W. and P.J. Davies, P.J., 1979. Effects of elevated nitrogen and phosphorous on
coral reef growth. Limnol. Oceanogr 24: 935-940.
September 2009
D
10
CORALZOO
Levy, O., L. Appelbaum, W. Leggat, Y. Gothlif, D.C. Hayward, D.J. Miller, and O. HoeghGulberg, 2007. Light-Responsive Cryptochromes from a Simple Multicellular Animal, the
Coral Acropora millepora. Science 318: 467-470.
Leewis, R.J. and Janse, M. (editors), 2008. Advances in Coral Husbandry in Public
Aquariums, Public Aquarium Husbandry Series, Volume 2. Burgers' Zoo, Arnhem, The
Netherlands. 460 pp.
Mumby, P.J., A.J. Edwards, J.E. Arias-González, K.C. Lindeman, P.G. Blackwell, A. Gall, A.,
M.I. Gorczynska, A.R. Harborne, C.L. Pescod, H. Renken, C.C.C. Wabnitz, and G.
Llewellyn, 2004. Mangroves enhance the biomass of coral reef fish communities in the
Caribbean. Nature 427: 533-536.
Pritchard, D.W., 1967. What is an estuary: Physical view point, Estuaries. American
Association for the Advancement of Science, Washington D.C., USA, 83:3-5.
Riddle, D., 2009. Feature Article: How to Make Corals Colorful, Part One: New Information,
with Particular Attention to Blue-Green Fluorescent Pigments. Advanced Aquarist's Online
Magazine 8.
Robertson, A.I. and N.C. Duke, 1990. Mangrove fish-communities in tropical Queensland,
Australia: Spatial and temporal patterns in densities, biomass and community structure.
Marine Biology 104: 369-379.
Schutter, M., B. van Velthoven, M. Janse, M., R. Osinga, M. Janssen, R.H. Wijffels and
J.H.J.Verreth, 2008. The effect of irradiance on long-term skeletal growth and net
photosynthesis in Galaxea fascicularis under four light conditions. J. Exp. Mar. Biol. Ecol.
376 (2):75-80.
Schutter, M., J. Crocker, A. Paijmans, M. Janse, R. Osinga, J. Verreth and R.H. Wijffels,
2009. The effect of different flow regimes on the growth and metabolic rates of the
scleractinian coral Galaxea fascicularis. Submitted.
Veron, J.E.N. and M. Stafford-Smith, (eds.), 2000. Corals of the world, Volume 1. Australian
Institute of Marine Science, Australia, pp 463.
Walter Dorriné, 2007. University of Antwerp (Belgium), personal communication.
September 2009
D
11
CORALZOO
3.3.1. PROTOCOLS
CORALZOO WORK PROTOCOL
3.3.1.1. Cleaning
Acquired at Oceanario de Lisboa, Lissabon, Portugal
Basic information provided by(Elsa Santos and
Contact: Elsa Santos
Núria Baylina
e-mail:
esantos@oceanario.pt
e-mail:
nbaylina@oceanario.pt
Introduction
Although coral systems don’t need a great deal of cleaning, it is important to control algae
growth and to remove the excess of sediments that results from the chemical/biological
reactions that occurs in the system.
Materials





Hose
Siphon
Cleaning pad
Window sucker
Brushes
Procedures






The coral tanks are dived weekly to be cleaned.
The surface layer of the bottom sand is siphoned. And a 4-5% of water change is
done during this procedure.
In one of the tanks all the decoration is “washed” with an Eheim pump, in order to
remove all the sediments that deposit inside the rock.
Macroalgae and microalgae are scrubbed from the rockwork and live rock.
In the end the acrylic is cleaned.
During diving a close look is given to the corals in order to check them.
September 2009