Why are the coral reef exhibits in aquariums mostly artificial?

Answer 1

Because an artifial coral is so much easier and less expensive to maintain. A rubber coral does not need special lighting or special food / feeding schedules. They can't "die" and they cost less than a living coral does.
Plus, you can find some pretty realistic looking fake corals. They don't replace the real thing, of course, but they do the trick.

Answer 2

Artificial or resign corals are much lighter. This is a big Plus when building an artificial reef for display.

However the main reason is, an aquarium is an enclosed system. Live rocks and corals can die off due to changing water quality. This will reak havock on the entire tank. This can quickly overload the entire system! Even top quality, fully cured live rock can be quickly turned into dead base rock. Especiall if mass quantities are introduced or installed all at once.

As with the ocean, Corals are built up over time. Old dying new forming. The ocean currents and waves continuously flush the water keeping old decaying corals (ammonia and nitrates) levels from becoming too high there for killing the rock or corals beneath it.

In a tank system the same applies, the introduction of too much live rock or coral reef pieces at one timecan quickly kill the rock and organisms living in and on it killing everything in the tank.

Having a good mix of dead and live is much easier to regulate in an aquarium.

Expense has nothing to do with why the aquarium reefs are built this way.

Answer 3

Danielle Z is correct. The main reason for artificial displays is due to the dieing off of the rock, time for setting them up and changes water quality. The ocean naturally moves high nitrate and ammonia waters and dispurses them quickly.

When corals or live rock dies, just like a fish, will cause spikes in water quality potentially killing the entire tank.

Did you ever see the "Glued on rocks" they have at Petsmart?

Answer 4

Because reefs are very difficult and expensive to maintain on that level, and the exhibits are usually targeted toward the fish and creatures.