Transcript Fish Tanks/Aquariums

Aquariums/Tanks
Dr. Craig Kasper
• Many people have owned or will own a fish tank
(it may even contain fish)
• As we will see, aquariums for fish take on
many forms...some are simple.
• Some are a bit more complex...
Aquariums: What are they?
• An aquarium (plural aquariums or
aquaria)
• Clear-sided container
• Typically glass or high-strength plastic
• Houses plants and animals, or both.
• Private and public display
• Aquarium keeping is a popular hobby (>60 million hobbist globally)
• Recognized as early as the1850s, when the predecessor of the
modern aquarium was first developed as a novel curiosity,
• Public aquaria reproduce the home aquarist's hobby on a grand
scale — the Osaka Aquarium (seen here), boasts a tank of 1.4
million gallons and nearly 580 spp.
• Currently, huge variety exists!
• A simple bowl housing a single fish to complex
simulated ecosystems with carefully engineered support
systems.
• Fresh or salt water, tropical or cold water.
• Wild collecting still an issue, esp. salt H20
(REM:ornamental fish?)
The Florida Aquarium
• Must maintain a tank ecology that mimics
natural habitat.
• Controlling water quality!
managing the inflow and outflow of nutrients,
management of waste (nitrogenous)
beneficial bacteria populations.
Aquarium Parts
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Tank
Filter
Gravel/sustrate
Pump
Aerator
Reliable water supply
Tanks
• High quality glass
-Plexiglass is expensive, but lighter
Monteray Bay Aquarium
Plexiglass offers unique design options!
No one wants this much water on the carpet!!
Courtesy: Perigrine Plastics
Production Tanks
• Production tanks can
be made of fiberglass,
wood, etc.
• Volume necessary
and strength, not
aesthetics!
St. Croix Waters Fishery
Mote Marine Laboratory
Mote Marine Laboratory
Filters
• Primary method of cleaning tank
• Removes solids
-small solids called “suspended solids”
-larger ones called “flocs”
• Provides substrate for nitrifiers
• Many types depending on needs
Gravel/Substrate
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Material for nesting
Aesthetics
Nitrification
“Live sand”
Filtration
Gravel/Substrate
Gravel/Substrate
PVC shavings!
Activated Carbon
Media Filters
• Bead/Sand/Media filters all use water pressure
to force water through some type of media.
• Excellent filtering capacity, esp. for larger
systems
• More maintenance (media changing
backwashing, etc.)
Mixed media filters
Gravity Filtration
• Trickle filters/Settling Chamber/Swirl Separators
• Most use gravity to accomplish filtering.
• Better for nitrification and oxygenation.
• Prone to clogging if primary filtration inefficient.
Screen Filters (RDF)
• Screen/Microscreen filters
• A.k.a.—rotating drum filters
• Utilize large particle size
“flocculation” to remove
solids.
• Excessive flow can
reduce efficiency!
Best of Both Worlds??
• “Fluidized” bed??
• Actually more simple than it sounds.
• Running a sandfilter backwards would give
same effect.
• Huge potential for nitrification.
• Bed expansion by optimizing flow.
Fluidized-Bed Filter
• Media maintained ~ 50-100% expansion
volume of original.
Over 20 feet tall!
Bead Filters
• Another form of “fluidized”
filter system (upwelling).
• Media is usually plastic beads.
• Good nitrification.
• Performs poorly during heavy
loading.
-excessive stocking density
-ad libitum feeding
Aeration
• Oxygen
• Speeds up decomposition
• Circulates water (air lift pump)
Aeration
Non-pressurized
Downflow bubble contactor (DBC)
Counter current diffusion column
U-tube diffusers
DBC
U-tube
Biofilters
•Help to establish nitrogen cycle.
•Break down toxic fish wastes.
Liquid Oxygen
Ozone
• Facilitates higher densities
• Increases flocculation
• Cheaper than gas O2
• Increase O2 saturation
• Reduces disease outbreak
-kills bateria, fungus,
viruses
• Can increase CO2 levels
• Expensive!!
• False security?
-increased density
-increased solids
-may increase disease
Protein Skimmers/ Foam Fractionators
• Removal of excessive organics
-decreases B.O.D. and C.O.D.
• Increases flocculation
-decreases solids
-increases water clarity
• What really does the work??
Bacteria!!
How Do I Condition a Biofilter?
• Since nitrifying bacteria are ubiquitous (everywhere) and
can be found easily in the water column, soil and
sediments you can just add some pond water or a little
dirt to the system. (Could introduce pathogens or other
toxins though.)
• A better way…
a. Use existing media from another filter as a starter
colony (just like passing around grandma’s sour
dough starters).
Recipe for Nitrification Success!
• Once you’ve achieved proper ph,
hardness, and alkalinity for your target
species; it’s time to add the bacteria
before you stock out.
• System start-up formulae:
a. Spike the system with ammonia.
-(NH4)SO4
3.3 ppm (mg/L)
-NH4Cl
3-6 ppm (mg/L)
b. Place several fish in the system and feed them.
Wait 4 weeks (if no starters present)…presto!
Get ‘em yourself!
(Sewage treatment
inspectors get top
pay!!)