Fish Husbandry Flashcards
How would you describe the distribution of fish?
Vertical, found all over the world
What is present in a fish’s blood to allow them to deal with sub-zero temperature?
Antifreeze
What are the 3 water salinity types that a fish could be found in?
- Freshwater
- Brackish (slightly salty e.g. rivers)
- Marine
How can oxygen requirements vary between fish species?
- some need cold, O2-rich streams
- some survive in high altitude warm springs
- some survive 3 months without O2 in ice-covered ponds and lakes
What are the main husbandry requirements that need to be considered when keeping fish?
- Oxygen
- Temperature tolerance
- Salinity
- pH requirements
- Space/size of tank
- Behaviour/aggression
- Health
What are 4 husbandry requirements of Rainbow trout?
- Freshwater
- Optimum temp 18 degrees
- Benefit from fast flowing water
- Aggressive predator
Give 4 husbandry requirements of Sea bass
- Marnie
- pH 7.6-8.4
- Optimal temp = 12 degrees
- Social and fast growing
Which problems mean that filtration is vital for fish health in a tank?
- Fish release ammonia as metabolic waste, this is very toxic
- Faeces and other solid waste decays in the water
- Clouds the water
What are the 3 sequential sections of a filtration system?
- Mechanical
- Biological
- Chemical
Which 4 features make up mechanical filtration?
- Filter mats
- Swirl filters
- Sand filters
- Brushes
What is the aim of biological filtration?
Encourage the growth of beneficial autotrophic bacteria which will breakdown the toxic nitrogenous waste via nitrification
In biological filtration, what is ammonia broken down into? Which bacteria are involved in this process?
Ammonia -> (Nitrosomonas) -> Nitrite -> (Nitrobacter) -> Nitrate
What is the aim of chemical filtration?
To remove/adsorb specific undesirable substances from the water
Which 3 chemicals are used in chemical filtration?
- Carbon granules to remove ‘colour’ from the water
- Zeolite can remove ammonia
- Phosphate removing granules prevent algae growth
What are the 3 approaches of fish management? Which is the most intense?
Open
Semi-closed
Closed = Most intense
Describe an open fish system
Caged environments in e.g. rivers, lakes estuaries, open sea.
Lack intensive water quality management, rely on the natural system to maintain water quality.
Can have very low or very high densities of fish.
Sea bass, salmon
Describe a semi-closed system
Flow-through or once-through systems, or raceways.
Inland aquaculture.
Inlet and outlet, fast continuous water flow
Allows high densities of fish
Describe a closed system
Recirculating aquaculture systems RAS Water re-conditioned and recirculated Marine and freshwater High fish densities Minimal water and land use Highly controlled growth conditions Needs very efficient bio-filtration Expensive to set up and maintain Needs highly trained staff
What are some features of an ornamental tank set up?
- Filter
- Food
- Enrichment
- Oxygenator
- Thermostat
- Timed lights
