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Aquaria: Marine: 

How many of these staples of marine aquarium keeping past do you remember? How many still exist?

Gro-Lux fluorescents
Vita-Lite fluorescents
Vita-Lite PowerTwist fluorescents
Metal Halide
T-5 6500K and actinic fluorescents

Egg crate and screen undergravel
Nektonics undergravel
Lee's undergravel
Aqualogy undergravel and Power 200 and 400 power heads
Aqualogy Power 1, Power 300 and Power 600 power filters
Hagen 400 and 800 power heads
Vortex D1 Diatom Filter
Hawaiian Marine Angstrom UV Sterilizers
Sander ozonizer
Eheim cannister filters
Hagen Fluval cannister filters
Lifegard module filters
DynaFlo power filters
Hagen AquaClear power filters
Second Nature Whisper power filters

Sea Salt Mix:
Instant Ocean/Reef Crystals

Filter Media:
Kordon Bio-Mech

Air Pumps and Airstones:
Silent Giant
Metaframe Hush air pumps
Second Nature Whisper 100 - 1000
Tetra Luft air pump
Kordon Mist-Air airstones
RoToCo airstones
Lee's Discard-A-Stone

Rila pH Pebbles
Dolomite gravel
CaribSea crushed coral

All Glass
Atlas (Oceanic Systems)

Fish Foods:
Jungle Freeze-dried brine shrimp
Gamma frozen foods
San Francisco Bay Brand frozen brine shrimp
Kordon freeze-dried plankton and krill

Water Conditioners:
Jungle Start Right
Kordon Novaqua and Amquel

Filtration: General: 

Nitrification and denitrification are crucial processes in maintaining water quality within a marine aquarium. They are responsible for converting harmful nitrogenous waste compounds, such as ammonia and nitrite, into less toxic forms. Here's a detailed explanation of each process:


Nitrification is a two-step aerobic process that occurs in the aquarium's biological filter, primarily in the presence of beneficial bacteria. These bacteria convert toxic ammonia (NH3) and nitrite (NO2-) into relatively harmless nitrate (NO3-). The two steps involved in nitrification are:

a. Ammonia Oxidation: Ammonia-oxidizing bacteria (AOB), such as Nitrosomonas, convert ammonia into nitrite. This process is known as ammonia oxidation or ammonification and is represented by the following equation: 2 NH3 + 3 O2 → 2 NO2- + 2 H+ + 2 H2O

b. Nitrite Oxidation: Nitrite-oxidizing bacteria (NOB), such as Nitrobacter, further oxidize nitrite into nitrate. This step is called nitrite oxidation and is represented by the following equation: 2 NO2- + O2 → 2 NO3-

The nitrification process is essential for maintaining low levels of ammonia and nitrite, which can be highly toxic to fish and other aquarium inhabitants.


Denitrification is a biological process that occurs under anaerobic conditions, primarily in the substrate or in areas with limited oxygen availability within the aquarium. Denitrification helps reduce nitrate levels by converting nitrate (NO3-) into nitrogen gas (N2), which is released into the atmosphere. Denitrification involves several steps carried out by different groups of bacteria:

a. Nitrate Reduction: Nitrate-reducing bacteria (NRB) convert nitrate into nitrite, nitric oxide, and eventually nitrogen gas. The process can be represented by the following equation: 2 NO3- → 2 NO2- + O2 (nitrate reduction)

b. Nitrite Reduction: Nitrite is further reduced to nitric oxide (NO), nitrous oxide (N2O), and eventually nitrogen gas (N2). The equation for nitrite reduction is: 2 NO2- → 2 NO + O2 (nitrite reduction)

c. Nitric Oxide Reduction: Nitric oxide is reduced to nitrous oxide by nitric oxide-reducing bacteria. The equation for this step is: 2 NO + 2 H+ → N2O + H2O (nitric oxide reduction)

d. Nitrous Oxide Reduction: Nitrous oxide is finally reduced to nitrogen gas by nitrous oxide-reducing bacteria, represented by the equation: 2 N2O → 2 N2 + O2 (nitrous oxide reduction)

It's worth noting that denitrification occurs in areas of low oxygen concentration, such as deep within the substrate, dead spots, or within specialized anaerobic filter media.

In a marine aquarium, it is crucial to maintain a balance between nitrification and denitrification processes. This can be achieved by providing adequate surface area for beneficial bacteria colonization, proper oxygenation, and ensuring areas with limited oxygen for denitrification to take place. Regular monitoring of water parameters such as ammonia, nitrite, and nitrate levels is essential to ensure the overall health and well-being of the aquarium inhabitants.

Aquaria: Marine: 

Many things marine aquarists today take for granted were unthinkable in the nascent days of the hobby, just over half a century ago. In the early to mid-1970s, saltwater aquariums were only kept by the most intrepid and resourceful of individuals.

Very early on, synthetic sea salt mixes were non-existent. You "might" be able to concoct a formula by contacting a large public aquarium for information, then a chemical supply house for the requisite components. But, a hobbyist in New Orleans named Harry Freiberg was able to solve this by flying a helicopter carrying 55-gallon drums several miles offshore in the Gulf of Mexico and collecting natural seawater. The distance from shore helped to insure full salinity, and reduced the chances of the water containing pollutants often found in the waters closer to the coast.

This practice of using natural seawater was common among aquarists living in the tropical areas native to the types of ornamental marine fish sought by such hobbyists. But, using natural seawater meant first keeping it in opaque containers in total darkness for months in order to kill off any micro-organisms present in it.

One of the first widely available synthetic salt mixes, Instant Ocean, was produced by Aquarium Systems in Mentor, Ohio, and it was they who Mr. Freiberg would call upon to assist him in his endeavors, even going so far as to travel to his home in New Orleans to build undergravel filtration into the impressive in-wall display tanks in his den.

And an impressive display it was. Three large, acrylic aquariums side-by-side, each six feet long by three feet wide by four feet deep spanned the length of his den wall. Mounted with their bottoms at four feet above the floor, the installation dominated the vaulted-ceilinged room.

The filtration Aquarium Systems built for Freiberg would be of the type that would become ubiquitous in the early days of the saltwater hobby: plastic "eggcrate" lighting grid raised off the bottom of the tank, covered in fiberglass window screen, and powered by airlifts made of glass panels walling-off the rear corners of the tank. A dozen or more "Silent Giant" air pumps powered it all.

The massive tanks were actually housed in a structure built onto the side of the house by Freiberg specifically for the purpose. The tanks sat on a concrete slab raised up on cinder block walls. In an open area underneath sat a 125-gallon quarantine tank.

At the far end of the room was a 100-gallon Nalgene drum for mixing up the synthetic seawater. A pump and PVC piping led to an overhead nozzle which swiveled to reach each of the three aquariums. A library style ladder rolled the length of the room to allow Freiberg (or his employee) to access the tanks for feeding, etc. A drain in the floor simplified partial water changes by allowing siphoned water to be direct toward it.

On the aquarium room wall opposite the tanks sat a bench with water quality testing supplies (and even a microscope). Next to it were situated a 55-gallon aquarium housing feeder goldfish (to feed the trio of massive volitans lionfish) and a specially-made pallet, precisely sized to hold 6 cases of Instant Ocean salt mix safely off the often-wet floor.

The aquarium room had it own heating and air conditioning, so in-tank heaters were unnecessary. Lighting was suspended from the ceiling, so as to be able to freely access the tanks.

The aquarium inhabitants were typical of the era: mostly fish and a few invertebrates including banded coral shrimp, and anemones for the clownfish. The successful keeping of live corals was still years, if not decades, away. But all the fish were long-lived and had attained sizes rarely seen in typical home aquariums.

Freiberg passed away peacefully at age 97 in 2014 at the Uptown New Orleans condo in which he had lived for several years. Whether or not the tanks still existed at the time of sale, or if the buyers of his Bayou St. John home retained them if they did, is unknown.