Tank Preparation: Speaking the Language

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Tank Preparation:
Speaking the Language
Dr. Craig Kasper
Photo: Larry Ward
Golden Rules
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Relax. (This will be a journey, not a cruise.)
Be patient. Fish die once. Do it right first time.
It can take time (up to 6 weeks) for a new tank to mature.
Do not over stock or overfeed.
Research your fish before you get them.
Don’t get fish from a tank with dead/diseased fish in it.
Routine maintenance and documentation avoids dead fish.
Sometimes fish just die!
Have some fun!
• 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.
Summary: The Basics
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Choosing the right tank
Positioning the tank
Setting up the tank
The running in period
New tank syndrome
Water changes
First fish
Fish to avoid
Maintenance
Summary: Beyond the Basics
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Aeration
Water chemistry
Salt. Yes, or No?
Filters and Filtration
1. Tank Selection
• Match the tank to the size (and type) of fish you
will produce.
• Large fish (or deep bodied) need larger tanks.
• Convict cichlids can be placed in small tanks.
• Paddlefish or sting rays need wide tanks to turn!!
Tanks
• High quality glass
-Plexiglass is expensive, but lighter
Monteray Bay Aquarium
2. Tank Positioning
• REM: Water is very heavy!!!
Water @ 8.3 lbs. (3.8kg) per gallon (L)
Gravel @ 10 lbs/ft2
Glass tank (200 lbs)
Lid (~20 lbs)
Potential trouble!!
• Make sure the floor will support this weight!
• The floor beams are strongest
near the wall.
Tank Location
• Don't site the tank near a door (bang!)
• Avoid people traffic unless passage is wide!
• Radiators, sunlight add heat (algal growth)
• Convenient power supply.
• Will maintenance be easy (possible)?
No one wants this much water on the carpet!!
Courtesy: Perigrine Plastics
3. Tank Setup
• Place the tank stand; check plumb (level)
• Place some polystyrene over stand; place tank. (This
provides even support.)
• Place your equipment in the tank (heater, filters, power
heads lighting etc)
• Wash and place the gravel. (Recheck to make sure it is
still level.
• All electrical connections should be away from any water
at this point.
Tank Setup (cont.)
• Fill the tank about 1/3 full (check that it is still
level.)
• If it’s plumb, add hard landscape (stones
bogwood etc), continue filling until full.
• Switch on all electrical stuff and make sure
everything is working.
• Let run 24 hours to stabliize temperature.
• Don’t add fish yet…you’ve go no bacteria.
3. Tank Maturation
• Biofilter conditioning will now commense!
• Your water initially will be nearly sterile, esp. if you used tap water.
• We need nitrifiers to process fish wastes.
Nitrosomonas (ammonia to nitrite): NH3 → NO2-
Nitrobacter (nitrite to nitrate): NO2- → NO3-
Denitrifiers, Pseudomonas (nitrate to nitrogen gas): NO3- →N2
“New Tank” Syndrome
• In a new tank ammonia accumulates for 3 to 7 days where it
becomes very toxic.
• Fish death.
• The easiest thing to do to deal with this problem is to avoid it all
together.
• Maturing the tank before the fish go in it.
• If you develop high ammonia levels, stop feeding, change as much
water as needed to reduce your ammonia levels to near zero.
• Clean the gravel (even before you change the water.)
How Do I Condition a Biofilter?
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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.)
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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.
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-(NH4)SO4
3.3 ppm (mg/L)
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-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!!)
4. Water Changes
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The importance of carrying out regular partial water changes cannot be over
stressed.
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Even with good biofiltration, nitrates accumulate, but aren’t removed.
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All changes should be done gradually (~30%/month).
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Match incoming water with tank temp and pH.
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Large fish or carnivorous ones require more frequent water changes.
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Keep the nitrate level under 25ppm (<10ppm for breeding purposes)
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Also, adding makeup water replaces trace elements.
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Changing water doesn’t do much visually. But you won't breed many egg
layers if you neglect it, nor will you grow any fry to there full potential.
5. New Fish
Good 1st :
• cyprinids, Corydorus catfish and rainbowfish.
Good 2nd :
• loaches, dwarf pl*cos, tetras, cichlids, anabantids and livebearers.
Bad:
• goldfish, piranhas, knife fishes, hatchet and pencil fishes, elephant
noses and baby whales, Chinese algae eaters, bala sharks,
iridescent sharks, glass cats, pl*cos, long-whiskered catfish, redtailed catfish, spiny eels, painted glassfish, dyed fish, brackish fish
and saltwater fish.
(Basically, anything tropical, electrical, or that lives in special
water, isn’t a good starter!!)
6. Fish to Avoid
• Any fish that grows large!!
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Redtail Catfish (50kg)
Paddlefish (25kg)
Sturgeon (100 kg)
Wels Catfish
Arowana (>18’ for some spp.)
Arapima (2 meters)
The 'Dyed' Glassfish (injected Indian Glassfish).
7. System Maintenance
Daily:
• Fish alive ? Behaving normally?
• Remove all uneaten food, and any dead leaves from the plants.
• Check the temperature
• Check all the equipment, filters, heaters, pumps, etc.
Weekly:
• Check the pH
• Add “make up” water.
• Clean the glass (magnetic)
• Clean the condensation covers
Every Two Weeks:
• Carry out a partial water change of about 25 to 30%.
• Clean the substrate.
• Clean the filters.
• Carry out all water test.
Beyond the Basics
Aeration
• Oxygen: both fish and bacteria
Bacteria actually use up more oxygen than the fish.
(Pound for pound more than we do!!)
• Speeds up decomposition
• Circulates water (air lift pump)
• Ideally the airpump should be placed above the water
level (prevents back syphoning, quiets pumps)
• REM: Temp, TSS, and surface area
all influence O2 saturation.
Aeration
– Non-pressurized
• Downflow bubble contactor (DBC)
• Counter current diffusion column
• U-tube diffusers
DBC
U-tube
Water Chemistry
pH
• Most freshwater fish = 6.5-7.5 (marine: ~8.4)
• Improper pH can prevent fish from spawning.
• More acidic: add peat, more alkaline add
sodium bicarbonate.
Water Chemistry
Hardness
• Dissolved salts in the water (general hardness Ca2+ and Mg2+) and
carbonate hardness (CaCO3)
0 -- 50
50 – 100
100 – 200
200 – 300
300 – 450
> 450
Soft
Moderately Soft
Slightly Hard
Moderately hard
Hard
Very Hard
Trace Elements
• Usually they are added when you feed, but periodic checking may help
make the difference between raising 15 small fry, or raising 150 vigorous fry.
Excessive Water Hardness
• Fish which require soft water (some Amazon
fish) develop tough egg casings which prevents
them from fertilizing or hatching.
• Be carefull!!
Salt
• Don’t over do it.
• Too much salt in an aquarium can lead to
problems breeding fish, developing eggs, etc.
• Yes, salt can cure Nitrite problems, disease, or
reduce transport stress; but when you’re
breeding, try to avoid it.
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
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Media maintained ~ 50-100% expansion volume
of original.
Over 20 feet tall!
Bead Filters
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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
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