Ch. 1-4

Community freshwater

Ex: mollies, guppies, swordtails, gouramis, tetras, Corydoras, small pelcos, danios, loaches

Diagnosis start

Typical anatomy, behavior, water chemistry needs, and social structure

Pond fish

Ex: koi and goldfish

More aggressive spp

Ex: medium-large cichlids, large pelcos, piranhas (illegal in some states), carnivorous catfish

Single-pet spp

Aggressive spp, plus pacu and large catfish kept solo

Characidae (tetras) + Serrasalmidae, Gastropelecidae

Freshwater ornamental

Key ft: small, active egg layers: several hundred spp. Some (pacu, piranha, silver dollars), grow much larger.

Ex: neon tetra, cardinal tetra, black tetra, silver dollar, red-bellied piranha

Cyprinidae (carps and barbs)

Freshwater ornamental

Key ft: barbels on lower jaw; most lack adipose fin; egg layers, many easy to breed. Includes goldfish and koi

Ex: goldfish, zebra danio, tiger barb, rainbow shark, koi

Siluriformes (catfishes)

Freshwater ornamental

Key ft: 39 families, mostly freshwater, 2000+ species. All have barbels and are scaleless; some “naked,” others armored.

Ex: corydoras, pelcos, glass catfish, upside-down catfish

Cobitidae, Botiidae, and Gyrinocheilidae (loaches)

Freshwater ornamental

Key ft: similar ecology to catfish but longer, more rounded; some worm/eel-shaped. Many secretive, nocturnal

Ex: clown loach, kuhli loach, zebra loach

Poeciliidae (livebearers)

Freshwater ornamental

Key ft: give birth to live young rather than laying eggs; profilic breeders. Males often smaller, more color

Ex: guppy, platy, swordtail, sailfin molly

Cichlidae (cichlids)

Freshwater ornamental

Key ft: highly variable in size and temperament; often territorial and aggressive

Ex: angelfish, oscar, Jack dempsey, convict cichlid

Osphronemidae and Helostomatidae (labyrinth fish)

Freshwater ornamental

Key ft: posses a labyrinth organ (pseudo-lung) for breathing air; males often more colorful, build bubble nests

Ex: betta, dwarf gourami, paradise fish

Melanotaeniidae (rainbowfish)

Freshwater ornamental

Key ft: native to Aus, New Guinea, Indonesia; males brightly colored at maturity; good dither fish

Ex: boesemani rainbow, red rainbow

Popular pond fishes

Carps: koi, carp, goldfish, and tench

Popular tropical marine ornamental fish

More difficult to keep than FW. Require strict attention to water quality, environmental structure, and diet needs. Most in human care are wild caught; breeding is harder due to broodstock nutrient. Most are hermaphroditic

Pomacentridae (damsels and clownfish)

Marine ornamentals

Key ft: hardy, colorful, small. Clownfishes are protandrous hermaphrodites (male first); many are aquaculture

Ex: false clownfish, Clark’s clownfish, blue devil

Pseudochromide (dottybacks)

Marine ornamental

Key ft: smaller, elongated, bright coloration. Protogynous hermaphrodites (female first); semi-agressive

Ex: orchid dottyback, neon dottyback

Apogonidae (cardinalfish)

Marine ornamental

Key ft: hardy, 3-4in. Nocturnal, large eyes. Many are male mouthbrooders

Ex: banggai cardinal, pajama cardinal

Blenniidae (blennies)

Marine ornamental

Key ft: mostly lack swim bladder; bottom dwellers, Fang blennies have a buccal venom gland

Ex: bicolor blenny, lawnmower blenny

Cirrhitidae (hawkfish)

Marine ornamental

Key ft: bottom swimmers, no swim bladder; can be predatory on smaller fish

Ex: flame hawkfish, longnose hawkfish

Tetradontidae (puffers)

Marine ornamental

Key ft: do not keep with invertebrates; up to 12in; can be “nippy”

Ex: spotted green puffer, dwarf puffer

Gobiidae (gobies)

Marine ornamental

Key ft: many small (up to 3in), no swim bladder; some have fused pelvic fins forming suction disk

Ex: neon goby (a “cleaner fish”), fire goby

Callionymidae (dragonets)

Marine ornamental

Key ft: small, colorful, benthic. Wild-caught specimens can be hard to train onto commercial diets

Ex: mandarin goby/dragonet

Chaetodontidae (butterflyfish)

Marine ornamental

Key ft: many have specialized diets (algae, anemones, sponges, coral); not reef safe. 4-12in

Ex: copperband butterflyfish

Labridae (wrasse)

Marine ornamental

Key ft: large, varied family with protactile mouths. Most are protogynous hermaphrodites, haremic

Ex: cleaner wrasse, bluehead wrasse

Balistidae (triggerfish)

Marine ornamental

Key ft: need a large aquarium; strong crushing jaw; intelligent, aggressive, territorial

Ex: clown triggerfish, picasso trigger

Serranidae and Grammatidae (groupers and basslets)

Marine ornamental

Key ft: true groupers are large predators; basslets/anthias/grammas are small, planktivorous, reef-friendly

Ex: panther grouper, loyal gramma

Pomacanthidae (marine angelfish)

Marine ornamental

Key ft: more difficult to keep; protogynous hermaphrodites; larger species need 200-300+ gal

Ex: Queen angelfish, French angelfish

Acanthuridae (tangs and surgeonfish)

Marine ornamental

Key ft: sharp caudal peduncle spines, tough skin; specific dietary needs; some aquacultured

Ex: yellow tang, pacific blue tang

Popular non-fish aquarium spp

Freshwater: aquarium snails (Lymnaea, can be intermediate host for trematodes), shrimp (Neocarodina, Cardinia), crayfish

Marine: cleaner/candy cane/blood/coral-banded shrimps; anemone, hermit, and arrow crabs; sea stars; sea urchin; marine snails (Turbo, Astraea)

Laws and permits

Few laws govern keep a pet fish; restrictions mostly target protected/prohibited species or CITES-listed species. Most laws affect breeders, importers, and commercial aquariums. FDA and EPA (in US) regulate drugs and chemicals (including treatment pesticides)

Sexual dimorphism / dichromatism

Difference in shape / coloration between sexes

Protandrous hermaphridite

Develops as a male first, may later become female

Protogynous hermaphrodite

Develops as a female first, may later become a male

Agastric

Lacking a true (acid-producing) stomach

CITES

Convention of International Trade in Endangered Species

Circulation

Moves water through the system; can be arranged in series or parallel filtration circuits

Mechanical filtration

Captures solids; filter type depends on particle size (settleable, suspended, fine/dissolved)

Biofiltration

Converts toxic nitrogen waste via the nitrogen cycle

Aeration

Adds dissolved oxygen via air stones or surface agitation

Degasification

Removed CO2, H2S, and excess nitrogen gas by increasing air exposure

Disinfection

Kills:inactivate pathogens (UV sterilization is more common and safer than ozonatiom); mostly used in public aquaria and commerical aquaculture, not typical hobbyist tanks

Nitrogen cycle

1. ammonia-oxidizing bacteria (AOB) and archaea (AOA) convert ammonia to nitrite (also toxic), using oxygen and bicarbonate

2. Nitrite-oxidizing bacteria (NOB) convert nitrite to nitrate (much less toxic)

3. Some Nitrospira spp. (“Comammox”) can completely oxidize ammonia directly to nitrate

4. Other anaerobic microorganisms can assist with ammonia and nitrite removal when present

5. Denitrifying bacteria (more common in anaerobic zone) transform nitrate into nitrogen gas

6. Plants and phytoplankton take up ammonia and nitrate for growth, helping remove them

7. Most common biofilter bacteria work best in pH range of 7.0-8.5

Ammonia (NH3/UIA)

The un-ionized form is toxic; NH4+ is far less toxic. High pH and high temp both increase toxicity (UIA fraction). Marine fish more susceptible than FW. Treat with 30-50% water change or dechlorinated water every 12-24hrs

Nitrite (NO2-)

Harmful above 0.1mg/L. Less of a problem in marine systems. Mitigate with 30-50% water change and add ~1g/L salt to raise chloride.

Not all right.

Nitrate (NO3-)

Much less toxic. General target <30mg/L. Reduce with water changes, denitrification, or planted refuge in.

Is great (in comparison to other form)

Alkalinity (KH)

Buffering capacity against acid, measured as mg/L CaCO3; freshwater range 50-250mg/L. Bicarbonate is the primary buffer; depleted over time as ammonia oxidized and acid accumulates. Raised with crushed coral, dolomite, or baking soda

Hardness (GH)

Total divalent cations (mainly Ca2+ and Mg2+); reduce with peat or dilution with softened/RO water

Specific gravity

Measured with refractometer or hydrometer

Tank essentials

Size: small tanks (<30gal) change quality faster and are harder to manage; larger tanks need more filtration and support

Light: full spectrum light is ideal for plants; incandescent bulbs are inefficient and produce heat

Cover: tight fitting hood to prevent fish escape

Heater: ~4 watts/gallon; broken heaters can release stray voltage

Aeration

Dissolved oxygen decreases with higher salinity, higher temperature, and lower atmospheric pressure. Test DO just before dawn, when levels are lowest

New tank cycling

1. Fishless dosing: add ammonia; keep dosing as ammonia drops to zero

2. Seed the biofilter: add commercial nitrifying bacteria or media/water from established disease-free tank

3. Hardy fish, gradual stocking

Old tank syndrome

Hardness/toxin buildup and alkalinity/pH decline in tank that are only topped off and never truly water-changed

Nitrification

Ammonia to nitrite to nitrate

(aerobic)

Denitrification

Nitrate to nitrogen gas

(Anaerobic)

Carbohydrates

Not required by many fish; goldfish/koi use hindgut fermentation to digest complex carbs; other species excrete plant matter undigested

Fats

Main source of dietary energy; keep to no more than 15% of daily intake to avoid hepatic lipidosis

Protein

Usually the largest % of dry matter in commercial diets; excess breaks down into toxic ammonia/nitrite. Animal protein supplies all 10 essential amino acids; plant protein may need lysine, methionine, threonine supplementation

Vit A deficiency

Exophthalmia, eye-lens displacement, edema, corneal changes, skin depigmentation

Vit D deficiency

Tetany of white skeletal muscles, impaired calcium homeostasis, low bone ash

Vit E deficiency

Skin depigmentation, hemolytic anemia, muscular dystrophy

Vit K deficiency

Prolonged blood clotting, anemia, skin hemorrhages

Thiamine (B1) deficiency

Muscle atrophy, convulsions, loss of equilibrium

Calcium/phosphorus deficiency

Reduced growth, poor bone mineralization, skeletal deformities

Iron deficiency

Microcytic anemia

Iodine deficiency

Goiter (thyroid hyperplasia)

Zinc deficiency

Depressed growth, skin/fin erosions, lens cataracts

Selenium deficiency

Muscular dystrophy (± vitamin E deficiency)

BCS 1

Thin/emaciated (head larger than body, concave ventral surface)

BCS 2

Under conditioned (head and body equal size)

BCS 3

Well conditioned (body larger than head, slightly convex ventral surface)

BCS 4

Over conditioned (body significantly larger than head, moderately convex)

BCS 5

Obese/large (significantly convex ventral surface, distended abdomen)

Flake/pellet storage

Cool, dry, and dark place; check expiration date; replace every 6-8months

Nutrient leaching

Water-soluble vitamins are lost from some flake diets within 30 seconds in water

Feeding amount for adults

1-3% body weight/day

Feeding amount for mature warmwater ornamentals

1.0-2.5% of body weight/day

Feeding amount for goldfish

0.3% of body weight/day

Hepatic lipidosis

Fatty liver disease, risked by excess dietary fat

Agastric

Lacking a true stomach (e.g., goldfish, koi, pipefish, parrotfish)

BCS

Body condition scoring, a semi-quantitative nutrients assessment tool

“Neighbor syndrome”

Well-meaning neighbors overfeeding fish while owners away

General feeding guideline

Feed once daily, no more than fish can eat in 3-5 minutes; estimating biomass and feeding specific % daily is preferred