Tank Preparation: Speaking the Language Dr. Craig Kasper Photo: Larry Ward Golden Rules • • • • • • • • • 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 • • • • • • • • • 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 • • • • 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? • 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!!) 4. Water Changes • The importance of carrying out regular partial water changes cannot be over stressed. • Even with good biofiltration, nitrates accumulate, but aren’t removed. • All changes should be done gradually (~30%/month). • Match incoming water with tank temp and pH. • Large fish or carnivorous ones require more frequent water changes. • Keep the nitrate level under 25ppm (<10ppm for breeding purposes) • Also, adding makeup water replaces trace elements. • 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!! • • • • • • • 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 • • • • • 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