Animal SelectionA. Criteria for selecting organisms:

1. immediate condition2. potential survivorship3. ease of care4. compatibility with other animals5. potential for growth

Immediate ConditionI. Fins and fin rays

Rays: support the fins and some may be articulated (branched)

Single fins:A. dorsal fin (top)B. anal fin (underside before tail)Keep fish upright and act like keels

C. caudal fin (tail)Provides final drive through the water (power)

d. Adipose fin (behind dorsal)Only on some fish, no rays, and seems to have no

purpose

II. Paired fins: for maneuverability (like mammal limbs)A. pectoral fins (behind gills) All for spinning around, light fanning of water

over eggs, acts as brakes, used to dislodge food from bottom of tank

B. Pelvic fins (in front of anal fin)Acts like hydroplanes, used by females to carry

eggs to hatch site, some use to threaten enemies, some contain taste cells on tips to locate food

-fins should be intact-fin rays should be straight and unbroken-fins should be in normal positions (flat on body

= ill)-cloudy fins = bacterial infection

2. Skin:- unblemished, bright, shiny- White patches on eyes or skin, could be

bacterial disease- Mucus coating should be transparent and not

obvious (protects from parasites and gives slipability)

- Scales missing around head or lateral line = disease

3. Signs of starvation: (should have well filled out body contours)

- Fish with a rounded or torpedo shaped body could have full bellies yet starved (if have not eaten in 2-3 days, could still die of starvation)

- Fish that are compressed laterally (pinched appearance) have lost weight between spinal column and dorsal fin

4. Behavior:-swimming motion straight-ability to stay straight and perfectly still at will-breathing slow and regular-winner of territorial disputes (not hanging

around in upper corners or with ragged fins)

-sea anemones with tentacles fully extended (irritated or out of H2O for long time if curved inward)

-sea urchins with spines erect-starfish active-move about smoothly-picking food up off bottom (adjusting)

Survivorship:Projected longevity or probability of surviving

FishLife Span (just examples)Black tip reef shark 20 years (still alive)Clark's clown 8y 4mCuttlefish1 3 monthsDiamond butterflyfish 12 yearsGiant Pacific Octopus 27 monthsNeon goby 4 ½ years

1. Factors that influence survivorshipa. chemical imbalances in H2O (pH, nitrates,

nitrites, salinity, other)B. social factorsC. captivity history

- Starvation- Exposure to disease (dead fish in tank)- Age (humped back = old)- Newness to store (2-3 weeks in stock)

2. Common MistakesA. buying species with specific food

requirementsEx. Butterfly and angelfish only eat coral

mucus or living sponges, Parrotfish only eat algae growing on dead coral (not hardy), Tangs and sturgeon fish adapt quickly to aquarium diets

B. Voracious species jeopardize the survival of smaller species

C. single gregarious fish should not be purchasedE. metals can contaminate tankF. poisons of atmosphere (lotion, soap, perfume,

etc)G. neglected filtersH. pre-cast concrete decorationsI. dyes of colored gravelsJ. buying organisms with low nitrate tolerance

(live coral)

Ease of CareA. look for species that adapt easily to

aquarium life and require little special careB. Look for species that resist infectious

diseases will and accept food readilyExample: Freshwater Angelfish are more

prone to Mycobacterial infections than other types of fish.

Compatibility with Other AnimalsA. Select animals likely to coexist peacefullyB. aggression should be limited to brief

chases without injuryC. limited space and shelter can increase

aggressionD. shape can trigger aggression (competition

for food)-herbivores: deeper, flatter shape-carnivores: elongated and streamlined for

speed

E. Color: recognize own species = competition

F. same feeding behavior = competitionG. size: unless same food source, won’t

bother because won’t eat much

H. Intraspecific aggressions: against own species- Only buy one of species (angelfish and damsels)

Interspecific aggressions: against other species

- Water for chasing and damage (difficult to predict)- Introduce new species in dark and after feeding

tank (less aggression)

I. if aggression problem, rearrange the “furniture”

J. Decorations:

1. two functions:A. attractivenessB. provide appropriate living spaces for

animals2. Shape:

A. shelters big enough for small fish, shrimp, crabs, etc. with openings large enough for them to enter but too small for larger animals

B. avoid sharp-edged items

3. Composition: A. use plastic (environmentally friendly)B. if use natural items, rinse/boil firstC. avoid metals (often in plants)

4. Placement of Decorations:A. arrange with enough space to access

openingsB. push into gravel to avoid topplingC. place taller pieces in back to avoid

swimming disruption

Potential for GrowthA. excessive growth has same effect as over

stocking (too much waste)B. Animals outgrow their shelter spaceC. under stocking will diminish waste

problems and allow for adequate space for future growth and social interaction