THE FIN-ISHING TOUCH; CUSTOM AQUARIUMS OFFER DELUXE DIGS FOR TROPICAL FISH.

Byline: Hala Ali Aryan

Is your idea of an aquarium a plain glass bowl decorated with blue rocks and only a tiny plastic scuba diver to keep your goldfish company? Pshaw.

Instead of using plastic toys, fish tanks and aquariums now mimic Mother Nature's watery habitats with an array of real plant and fish life from around the world. Increasingly popular are biotopes, a kind of snapshot of a certain aquatic area of the world that can be re-created in a tank. Just think: You can create a whole tide pool in your bedroom with a sand bottom, starfish, sea cucumbers, anemones and urchins.

For a South American setup, customizer Ed Fernandez uses wood, a variety of aquatic plants and fish native to the waters in that area of the world.

What about the look of an African lake? Fernandez uses few plants and very hard water. Lakes in Africa are high in mineral content. A tank re-creating this environment will include shells, coral and fish that come in metallic shades of blue, red and yellow.

Some aquarium owners like to grow coral in their tanks. With well-placed lighting and the right kind of water, your fish could swim through a colorful and exotic reef.

A new, open-top aquarium allows plants to grow outside the tank itself, much like in their natural state.

Your own waterworld

To create an exotic underwater world in your home, you can enlist the help of aquarium customizers who will build an aquarium, according to your taste and budget.

John Farrell, owner of Fish Art in Chatsworth, has designed tanks large enough to hold 1,000 gallons of water. He built one aquarium into a headboard of a bed, and another housed black-tipped reef sharks.

A popular design is ``living art'' - a rectangular aquarium built into the wall and framed.

Such elaborate designs, which can be up to 16 feet long, can cost up to $35,000. Then there's Farrell's weekly or bimonthly service fee of $600 to $700 to clean the tank and tend to the fish, giving them medication as needed.

If the fish can't be treated either by putting medicine in the water or by applying it directly to their scales, he takes them to ``hospital tanks'' in his store.

``All the homeowners need to do is feed the fish,'' Farrell said.

Sea change

But even the best attempts at re-creating ecosystems in a tank won't provide a fully self-sustaining environment, Farrell said. Underwater habitats, such as coral, require a delicate balance of nutrients, light and temperature to thrive.

Top-of-the-line aquariums use high-tech gizmos that will help you re-create as closely as possible a true underwater environment. One product lets you simulate natural water currents, re-creating the gentle lapping of waves. Fernandez also has installed lighting systems that are programmed to match the lunar cycle so that your fish tank will be lighter or dimmer according to the phases of the moon.

In fact, these two gadgets can be connected so that the waves in your tank will coincide with high and low tides. Each of these runs from $100-$200.

But perhaps the most amazing environmental gadget is called the Octopus Controller, which combines both these gizmos and also regularly tests the water and controls the temperature and filtration system. You can connect it to your computer so you'll know what it has been doing, and it also can call you on your pager if anything goes wrong in the tank. This king of fish-tank toy goes for about $1,000. Does all this sound high-priced and frivolous? For most people, it is. But if you already have a lot of money invested in a tank environment, Fernandez said, the Octopus can help protect it.

If your pocketbook can't quite afford a fish tank that knows how to page you, there are plenty of simpler aquariums that are much more affordable.

Fernandez recommends that first, you do some research about the look you want for your tank and read up on the types of fish that will fit inside it. Make sure the fish you want have a good record for surviving in captivity. Some pet stores might sell fish that don't live very long in a tank, he said.

It's also important to make sure all the fish you're interested in are compatible. You don't want to put a fish in the tank with another species that likes to eat it.

He warns against incorporating sharks, sea horses and jellyfish in your tank. Sharks continue to grow as long as they are being fed and will always outgrow the tank they live in.

Sea horses are incredibly fragile and often are sick by the time they arrive in a store. They also require live food, which can be a hassle to buy and store. Fernandez predicts they will be banned for private sale in a few years.

Jellyfish are difficult to handle and keep alive.

But there are plenty of other interesting creatures that are fun and safe to keep. Along with all the hundreds of types of intriguing fish, there are small crabs and clams that thrive in a well-tended tank.

Find the right spot

After deciding on your tank theme and species, the customizer will come to your home to figure out the best location for the tank.

Some experts advise keeping the tank away from a window. Make sure it has its own power source. And the floor, of course, must be strong enough to support it - some of these biotopes can be pretty heavy.

Putting the tank against a wall or screen give the fish a place to hide. Hiding is important to fish - if they can protect themselves by hiding, they tend to be less stressed.

Tanks built into walls or sitting on stands against a wall are good choices. The height of a tank should not be more than the surface area.

One customer got particularly creative when he had Fernandez install a tank in the living room with a 4-inch pipe in the wall that flowed into a smaller tank in the bathroom. The fish could swim back and forth between the two rooms.

What's the rush?

After building and installing the tank and filling it with the appropriate water and chemicals, you must wait four to six weeks before adding the fish. This is where most people go wrong, because they want to buy everything at once and have an ``instant ocean.'' Fernandez said the water needs time to adjust so that it can sustain life.

For the first four to six months, the customizer makes house calls to make sure everything is working well and that the fish acclimate to their home, Fernandez said.

Ideally, once a tank is set up and running well, maintenance should take no more than 10 minutes a week, he said. Test kits for the nitrate, ammonia and phosphate levels are important. Changing the water - carefully - is probably the most vital maintenance task.

You can hand-feed the fish two or three times a week, or install an automatic feeder that regulates the times and proportions of their meals.

These customized aquariums can be whatever you wish to spend on them. Fernandez recommends purchasing the biggest tank you can afford. A good 60-gallon tank with a filter and light is about $100. A 60-gallon tank with freshwater fish and plants can range from $200 to $300, or more for exotic saltwater creatures. You also will be paying the customizer for the design and setup.

Buying and maintaining a well-stocked aquarium can be a big commitment of time and money - the price of living outside a fishbowl.

Daily News Staff Writer Jenifer Hanrahan contributed to this story.

CAPTION(S):

2 Photos

Photo: (1--Cover--Color) Fishing for compliments

Designer aquariums can add drama, color to your home

(2) Kim Boucher enjoys the 60-gallon fish tank she and her husband, Jack, built in their Rancho Cucamonga living room.

Greg Anderson