Life on Earth

Natural Reef Aquariums

Intense underwater gardening

The folks who know the most about reef ecology are the amateur reefers. These passionate hobbyists explore the essentials of marine life by creating artificial salt-water reefs at home. They can cram an amazing diversity of species – sponges, coral, mollusks, fishes — in a few square meters. The coolest residents are the invertebrates.. So much of this craft is like high-performance gardening. You’ve got grow-lights, pumps, salts, and lots of technical gear. Technology makes the chores not much more difficult than keeping fish. To handle this complexity, though, and the whims of dazzlingly strange creatures, veteran amateurs point to this book as the most helpful. The author stresses using the proper mix of reef organisms to filtrate the water without unneeded mechanics. He guides novices easily through sophisticated methods, keeping it as “natural” as possible. Because home reefer enthusiasts are so attuned to the life cycles of their captives, I learned more about marine life from here than any other source.

— KK

Natural Reef Aquariums
John H. Tullock
2001, 336 pages
T.F.H. Publications


Your grandfather, perhaps 100 years ago or so, could only imagine what wonders the world beneath the sea might contain. Your father could follow the exploits of the first explorers of the undersea realm and could just begin to see and experience the explosion of life on a coral reef. But you and I, we can not only visit this world whenever we wish, but we can also capture a small part of it in an oceanic microcosm of our own making in our own homes.


Even in the most northerly regions, an aquarium placed in direct sunlight can overheat. Aquarists should avoid placing the aquarium in a sunny window, as seasonal fluctuations in temperature in such a location will make maintaining the correct water temperature a challenge. Artificial lighting, for most home situations, is the better choice, being more controllable, predictable, and programmable for the most convenient viewing period.


Alternatively, organisms from deeper waters, or specimens that have languished for too long in dim light, may have ceased production of protective pigments. When these specimens are then placed under bright lights, the effect is similar to that experienced by someone who, having spent a long winter indoors, rushes out on the first sunny day and spends an afternoon sunbathing. I believe that the alleged burning of corals by metal halide lights can be attributed to a lack of understanding of how these organisms respond to light and not to any inherent detrimental effect of the lights themselves.


One of the more vexatious challenges, even for experienced reef keepers, is the appropriate placement of corals within the aquarium. Finding just the right level of light intensity and water motion can mean the difference between a specimen that thrives and grows, showing full polyp extension and brilliant coloration, and one that leads a lackluster existence, with polyps retracted or shrunken, dull coloration, and no growth.

Open (top) or closed polyps, as in this Palythoa colony, can be an indicator of water conditions. Constantly closed polyps are a sign of trouble.

Metal halide pendants provide intense illumination while permitting easy top-down viewing of the clam reef. A convenient acrylic sump houses the skimmer, heaters, pouches of activated carbon, and phosphate remover.


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