Fish Flashcards
What makes up the biggest proprtion of vertebrates?
Fish (34,000 species)
What should the pH of freshwater fish be?
6.5-8.5
What should the pH of marine fish be?
8.1-8.4
What should the temperature of coldwater fish be?
Range
What should the temperature of tropical fish be?
24-27
What are the two main types of pet fish?
Coldwater and Tropical
What is the biggest farmed fish in the UK?
Salmon
What is the legal requirement for every aquaculture business?
e.g fish farms
Must have a named vet attached to them
What are the main fish restocked?
course fish and carp
What should the pH of a tropical freshwater fish?
very variable, if this is not met then they will not thrive
What should the salinity of marine fish and invertebrates be?
Salinity 35ppt but should be marine salt
Why can fish cope with different temperatures?
range of isoenzymes, especially coldwater
tropical fish cannot thrive as well
Where does ammonia in a tank come from?
Produced and released through the gills
* can only be released provided there is less amonnium in the water- down the diffusion gradient
producedvia metabolism of fish
What is the secondary product of ammonium breakdown?
Nitrate
-free ammonia is the most toxic
ionised ammonia is less toxic
ammonia is oxidies into nitrite by bacteria then into nitrate
What should the alkalinity of a coldwater fish be?
100mg per litre
What is the effect of lights in the aquarium?
causes evaporation, water becomes saltier
What is the most critical factor for marine animals?
Dissolved oxygen
What does an increase in temperature do to the dissolved oxygen?
reduces oxygen solubility
What is the first indication of low oxygen?
lethargy and inappetence
What part of the fish can they use to gain oxygen?
The swim bladder
What may it mean if fish are dead first thing in the morning?
too much algae in the tank
What can nitrite cause?
Brown blood disease
What is the main function of biological filtration?
- exploit the nitrogen cycle
- removal harmful particles
What do fisheries use as their primary filtration system?
Aquatic plants
How much of their body weight do juvenile fish require?
5% of their body weight
What percentage of their body weight do adult fish require?
2%
When should you not be feeding your fish?
- Usually when you are away
- there are particles in the aquarium they can feed on
What is the effect of increasing temperature on oxygen?
Increased temp reduces oxygen solubility
What is the first indication of low oxygen?
lethargy and inappetence
What bacteria converts ammonia to nitrite?
Nitrosomonas
What bacteria converts nitrite to nitrate?
Nitrospira
What causes lamellar hyperplasia in fish?
Either due to stress of poor water quality (lots of ammonia)
Name 4 ways we can euthanise fish
- Overdose of aneasthetic
- Sharp blow to the head
- Stunning
- Eugenol/ Clove oil
