CORAL INTERVIEWS Pieter van Suijlekom

KORALLE editor Daniel Knop in conversation with Pieter van Suijlekom in front of his huge curved tank.

Pieter van Suijlekom of the Netherlands runs a company selling stoves and open-hearth fireplaces. That in itself would be of little or no interest to CORAL readers‚ were it not for a relevant attraction in the sales room. And in the truest sense of the word, it contains corals. And wrasses, surgeonfishes, shrimps‚Äîin short, everything that belongs in a reef aquarium. The aquarium in question is a 20-foot (6-m) long curved-front tank, which has to be one of the world's most outstanding private marine aquariums. We first portrayed this aquarium in CORAL Volume 5, Number 1 (Fire Corals), and we would now like to introduce you to the aquarist behind it and his newest reefkeeping plans. 

CORAL: Pieter, how long have you been fascinated by coral reefs, and when and how did you come to be involved in the reef aquarium hobby?

Pieter van Suijlekom: When I was in Boston in 1986, I visited a relatively small aquarium. It was a cool-water tank that contained only a few corals and fishes and was designed as a themed aquarium for the dwarf Peppermint Angelfish, Paracentropyge boylei. The sight of these lovely fishes is something I will never forget. It seems that shortly after my visit, this aquarium was decommissioned, as I never heard anything more of it.

In 1987 I went on holiday to the Maldives, and it was then that I decided to set up a marine aquarium in the sales room of my company. This tank measured 80 x 24 x 24 inches (200 x 60 x 60 cm).

In the 1980s, live rock could be obtained only with difficulty, and the majority of aquaria in the Netherlands contained mainly macro-algae‚ in part to regulate the nitrate content of the waters. The soft corals introduced initially were gradually replaced by Acropora, which was still quite unusual in those days.

Of course, back then the Internet, nowadays an extensive source of information, was not yet available, and so I had to obtain my knowledge mainly from books. I was influenced particularly by Charles Delbeek, whom I regard as one of the most influential pioneers of the reef aquarium hobby, but without overlooking other important authors.

Due to be torn down and rebuilt, the reefscape is becoming too crowded and overgrown with corals, its owner feels.

CORAL: A few years ago this magazine portrayed your impressive round acrylic tank, which undoubtedly set standards. Back then, I had the feeling that you were very happy with that aquarium and hence my great surprise when, only a few years later, I heard that you had shut it down in order to replace it with one of considerably larger size. How did that come about?

van Suijlekom: The history of it all is as follows: as you have mentioned, in 2000 we replaced the rectangular aquarium with a round tank 80 inches (2 m) in diameter and with a volume of 4,750 gallons (18,000 L). This project gave me a lot of pleasure over the years, and the first fish to go in, an Acanthurus achilles, is still swimming around today in the current aquarium. But when we refurbished the salesroom of our business in 2005, the round aquarium had to go.

It was replaced by a new tank 20 feet (6 m) long and with a curved glass front. One of the reasons for constructing an aquarium of so much greater size was the Acanthurus achilles mentioned above, which had far too little swimming space in the old tank.

CORAL: In order to give our readers some idea of how much equipment such an aquarium involves, could you please tell us how many HQI lamps and of what wattage you use for this tank?

Such a comprehensive community of living corals requires considerable expenditure on electricity.

van Suijlekom: The aquarium is illuminated using nine lamps of 400 watts (14,000 K) apiece, three lamps at 1,000 watts (14,000 K), and a single row of actinic tubes at 140 watts each, extending the entire length of the tank. The 400-watt lamps are in operation for nine hours daily, the 1,000-watt lamps for eight hours. All the lamps are replaced every six months.

CORAL: Impressive. How much time is needed to maintain such an aquarium? What volume are the partial water changes performed, and how often do you change water? Do you always use the same type of salt?

van Suijlekom: The aquarium requires about 20 hours per week for routine maintenance. That includes monitoring the water parameters and pruning the SPS corals when necessary. Because the aquarium is to some degree open to the public, the front glass and the sand have to be cleaned frequently.

The protein skimmer is cleaned every day in order to ensure optimal function. In addition the ten current pumps (Tunze Turbelle Stream: 5,000 to 8,000 gallons (20,000 to 30,000 L) per hour flow each) require regular attention as they would soon lose power if we didn't remove the dirt that in time clogs up their inlets.

There is permanent filtration over activated carbon, which is replaced every two weeks. Some 400 gallons (1,500 L) of the 2032 gallons (7,700 L) of water the tank contains are changed for fresh every week, and we use four different types of salt in order to avoid any deficiency problems. In addition, 400 gallons (1,500 L) of water are currently replaced with natural sea water once a month.

CORAL: Do you do this work all by yourself?

van Suijlekom: As well as the big main aquarium, the system comprises a seahorse tank with a volume of 92 gallons (350 L), one with a volume of 120 gallons (450 L) for azooxanthellate corals, and another, again with a volume of 120 gallons, for coral cuttings. Of course more aquaria also means more work, and it would be almost impossible for me to cope by myself given the scale of the operation.

Richard Westdorp is my helping hand; his knowledge and his abilities have made a significant contribution to the success of the system. Out of passion for the hobby he spends 10 to 15 hours here every week working on the aquaria, and without him it would be very difficult to manage an aquatic enterprise of this type.

CORAL: In our Aquarium Portrait, we indicated that even a refined aquarium system like this is not without difficulties. Could you please give us a brief summary of the problems, and above all the solutions to them?

van Suijlekom: In the first six months our main problem was with Bryopsis in the main tank, as these algae even began to grow on the corals. The plague was initially kept in check by the manual application of dozens of toothbrushes. Eventually the problem was resolved by adjusting the carbonate hardness to 13 and periodically raising the magnesium concentration.

But even now we still have to keep a watchful eye on the residues of this nuisance alga to make sure it doesn't get the upper hand again. It seems to be practically impossible to keep an artificial reef‚ especially one this size‚ completely free of this weed in the long term.

Pieter van Suijlekom's reef tank is widely regarded as of the world's most fascinating aquaria in private ownership.

CORAL: On the basis of your experiences with both small and large tanks: do you feel that a very large aquarium gives sufficient additional pleasure to justify the incredible expenditure involved, not only in terms of time, but also money?

van Suijlekom: Naturally one has to be quite clear right from the start how much time and money a major project like this will cost to bring to fruition, but this aquarium has repaid in full all that I have put into it. Every evening I sit for an hour in front of that huge front glass, and it is amazing how rapidly the stress of a hard day drops away in this setting. Plus I am of the opinion that it is the constant striving for bigger and better that makes our hobby so interesting.

CORAL: Humans keep on learning all their lives, especially if they are marine aquarists. Would you do anything differently if you were setting up the current aquarium with the benefit of hindsight?

van Suijlekom: To be honest, we are already in the process of making a number of changes. We are enlarging the equipment room to 32 square meters, building a new filter system, and adding extra aquaria with a total volume of 790 gallons (3,000 L), so that the system overall will have a total volume of more than 2640 gallons (10,000 L). In addition to the P20 protein skimmer from H&S we are installing a P30 protein skimmer from the same manufacturer.

By spring 2010 the big aquarium will have been in operation for five years, and I think it will by then be high time to break down the existing reef in order to avoid "old tank syndrome."

The fishes and corals will be housed for a while in the tank in the equipment room, so that we can rearrange the main aquarium. At the same time small scratches in the front glass will be polished away, and the back pane is to be fitted with blue acrylic. The current reef structure is too massive for my taste, and will be replaced by a more open rocky landscape consisting of four individual "islands." This will also make it easier to provide all the corals evenly with current, and in addition the impression of depth will be improved. The fish population will also be changed: fewer surgeonfishes, more angelfishes.

CORAL: The equipment for the big aquarium is housed in the cellar of the building. But anyone interested in water conditioning will find another aquarium there that will surely take his or her breath away.

Nobody who is familiar with the huge reef aquarium upstairs will be expecting a further tank below, set up as a dark, deep-reef aquarium and surpassing the big aquarium in its splendid colors. How did you come to be running such an extraordinary aquarium in the cellar, and what fascinates you so very much about deepwater corals?

The filter-feeder tank in the cellar equipment room is stocked with non-photosynthetic corals and is breathtakingly colorful but not normally accessible to the general public. It will serve as home to a pair of exceptionally rare pygmy angelfish.

van Suijlekom: The aquarium for the azooxanthellate corals is a 31-inch (80-cm) cube with 490-L (130-gallons) of water. It is sited in the equipment room in the cellar because that is the only way to keep it completely free from ambient light.

The reason why the aquarium needs to remain in a dark room will become clear if you think back to the start of this conversation: it is intended as a species aquarium for a pair of Paracentropyge boylei, which are already on order. The water temperature and the decor are designed specifically for these fishes. The aquarium will not be accessible to the public in order to avoid stress to these delicate and valuable fishes.

CORAL: Pieter, thank you very much for this fascinating glimpse into the world of your reef hobby!
 

Excerpt from the May/June 2010 Edition of CORAL. Subscribe today to read the full issue.