Aquariums/Tanks Dr. Craig Kasper

Many people have owned or will own a fish tank (it may even contain fish)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.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)An aquarium (plural aquariums or aquaria) Clear-sided containerClear-sided container Typically glass or high-strength plasticTypically glass or high-strength plastic Houses plants and animals, or both.Houses plants and animals, or both. Private and public displayPrivate and public display

Aquarium keeping is a popular hobby (>60 million hobbist globally)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,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.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!Currently, huge variety exists! A simple bowl housing a single fish to complex simulated ecosystems with carefully engineered support systems.A simple bowl housing a single fish to complex simulated ecosystems with carefully engineered support systems. Fresh or salt water, tropical or cold water.Fresh or salt water, tropical or cold water. Wild collecting still an issue, esp. salt H 2 0 (REM:ornamental fish?)Wild collecting still an issue, esp. salt H 2 0 (REM:ornamental fish?) The Florida Aquarium

Must maintain a tank ecology that mimics natural habitat.Must maintain a tank ecology that mimics natural habitat. Controlling water quality!Controlling water quality! managing the inflow and outflow of nutrients, management of waste (nitrogenous) beneficial bacteria populations.

Aquarium Parts Tank Filter Gravel/sustrate Pump Aerator Reliable water supply

Tanks High quality glassHigh quality glass -Plexiglass is expensive, but lighter Monteray Bay Aquarium

No one wants this much water on the carpet!! Plexiglass offers unique design options! 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

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 Material for nesting Aesthetics Nitrification “Live sand” Filtration

Gravel/Substrate

PVC shavings! Activated Carbon

Media Filters Bead/Sand/Media filters all use water pressure to force water through some type of media.Bead/Sand/Media filters all use water pressure to force water through some type of media. Excellent filtering capacity, esp. for larger systemsExcellent filtering capacity, esp. for larger systems More maintenance (media changingMore maintenance (media changing backwashing, etc.) backwashing, etc.)

Mixed media filters

Gravity Filtration Trickle filters/Settling Chamber/Swirl SeparatorsTrickle filters/Settling Chamber/Swirl Separators Most use gravity to accomplish filtering.Most use gravity to accomplish filtering. Better for nitrification and oxygenation.Better for nitrification and oxygenation. Prone to clogging if primary filtration inefficient.Prone to clogging if primary filtration inefficient.

Screen Filters (RDF) Screen/Microscreen filtersScreen/Microscreen filters A.k.a.—rotating drum filtersA.k.a.—rotating drum filters Utilize large particle sizeUtilize large particle size “flocculation” to remove “flocculation” to remove solids. solids. Excessive flow canExcessive flow can reduce efficiency! 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 ~ % expansion volume of original.Media maintained ~ % expansion volume of original.

Over 20 feet tall!

Bead Filters Another form of “fluidized”Another form of “fluidized” filter system (upwelling). filter system (upwelling). Media is usually plastic beads.Media is usually plastic beads. Good nitrification.Good nitrification. Performs poorly during heavyPerforms poorly during heavy loading. loading. -excessive stocking density -excessive stocking density -ad libitum feeding -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 U-tube DBC

Biofilters Help to establish nitrogen cycle.Help to establish nitrogen cycle. Break down toxic fish wastes.Break down toxic fish wastes.

Liquid Oxygen Facilitates higher densities Facilitates higher densities Cheaper than gas O 2 Cheaper than gas O 2 Increase O 2 saturation Increase O 2 saturation Can increase CO 2 levels Can increase CO 2 levels False security? False security? -increased density -increased solids -increased solids -may increase disease -may increase diseaseOzone Increases flocculation Increases flocculation Reduces disease outbreak Reduces disease outbreak -kills bateria, fungus, viruses viruses Expensive!! Expensive!!

Protein Skimmers/ Foam Fractionators Removal of excessive organics Removal of excessive organics -decreases B.O.D. and C.O.D. Increases flocculation Increases flocculation -decreases solids -decreases solids -increases water clarity -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.)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 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. -(NH 4 )SO ppm (mg/L) -NH 4 Cl3-6 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!!)