Discovery Aquariums Life Support System
Multiple Strategies Working Together
Biological Filtration-
Deep Sand Bed (DSB) - Bacterial processing and draw-down of nitrogenous
waste. Habitat for detritus feeders like snails, cucumbers, and sea stars. If the
detritus feeders have a comfy habitat, they will help clean the tank of dead
material and leftover food.
Wet/Dry Filter - “Trickle Filter” creates high oxygen environment for bacterial
processing of nitrogenous waste, filter media (sponges + biobale)
provide high surface area for beneficial bacterial colonization.
Refugium - Additional DSB action, controlled light-driven algae growth removes
nutrients from the water. This is good because nutrients + light = lots of unwanted algae growth.
Mechanical Filtration-
Sponges - remove particulate matter just like an air filter in your house.
Protein Skimmer - takes advantage of a neat physics trick: organic matter
(proteins etc) has a high affinity for bubbles; waste material “sticks” to bubbles. The protein skimmer generates millions of tiny bubbles, the longer the bubbles are in contact with the water before they pop, the more organic matter sticks to the bubbles. The bubbles float to the surface, spilling over into a collection cup, and as the bubbles burst the organic matter is left behind and you just dump it out!
Chemical Filtration-
Chemical Reactors - Granular Ferric Oxide (GFO) has a high affinity for binding with phosphate. Activated carbon has a high affinity for binding with silicate and phosphate, as well as other dissolved toxins (like those released by cnidarians-close relatives of anemones and corals). Phosphate and silicate are nutrients that can cause harmful algae to grow out of control, so it is important to remove them from the water as much as possible.
Ultraviolet Sterilization-
High intensity light in the high frequency, short wavelength range (ultraviolet)
shines on water as it passes through a protected chamber. The light kills any
microbes like harmful bacteria and viruses by giving them a really bad “sunburn”.
Temperature Control-
Powerful chillers cool water as it passes through, drawing heat away from the water and into the air in a similar fashion to the way a refrigerator works. This allows the water to stay at a chilly 50-55 degrees Farenheit.
The critters’ metabolism is adapted for life close to this temperature range, and maintaining a low temperature reduces the growth rate of harmful bacteria that can cause disease. These chillers have thermostats, just like air conditioning in a house, and the temperature can be maintained at a precise level.
Water Circulation- Pumps keep the water moving and disrupt an otherwise flat water surface, breaking up the surface tension and letting more oxygen dissolve into the water. Fish and invertebrates depend on this water movement and increased dissolved oxygen to breathe.
Summary- The different strategies of filtration and sterilization work together as a team to clean the water for tank inhabitants. Meanwhile, pumps keep the water moving and well-oxygenated and the chillers keep the temperature of the tank at a comfortable level.
