Loach

Ich (white spot disease)

SignsSalt-grain-like white spots on body and fins. Rubs body against sand or driftwood. Common after a drop in water temperature

PreventionKeep temperature changes within 2°C per day. Quarantine new fish in a separate container for 1–2 weeks before adding them

Fungal infection (saprolegnia)

SignsWhite cotton-like growth on wounds or around the mouth. Develops after jumping out or from abrasions on coarse gravel

PreventionUse fine sand with no sharp edges as substrate. If injured, isolate early in clean water

Aeromonas infection

SignsRed patches or bleeding on the skin, swollen belly, raised scales. Progresses to hole-like ulcers

PreventionMaintain water quality with a weekly 1/3 water change. Remove leftover food daily and avoid overcrowding

Columnaris

SignsMouth, fins and tail turn white, rot and fray. Progresses rapidly in hot summer water

PreventionKeep water at or below 28°C in summer. Isolate sick fish immediately; use separate nets and tools per tank

Oxygen deficiency / heat stress

SignsIntestinal breathing every few minutes. Gasps at the surface and does not return to the bottom. Sluggish

PreventionAdd aeration and a cooling fan in summer. Check the thermometer daily; never let it exceed 30°C

Indigestion / abdominal bloating

SignsSwollen belly; floats or cannot sink. No feces and refuses food

PreventionFeed sinking food in amounts eaten within a few minutes. Reduce feeding at low temperatures; never use old food

Jumping out and drying

PreventionSeal every gap in the lid and around cords and tubing. Do not startle. Keep the water level at least 5 cm below the rim

First aidCheck whether the body moves; gently wet it with tank water, mucus and all, and return it to the tank. Increase aeration, darken and keep quiet

Skin abrasions

PreventionFine sand only as substrate. Avoid sharp rocks and driftwood; do not chase with a net

First aidIsolate in clean water at the same temperature with a 0.3% salt bath. If white cotton appears, treat as fungus. Deep wounds: see a vet

Barbel damage

PreventionDo not use coarse gravel or sharp-edged substrate. Barbels rot in poor water, so keep up with water changes

First aidThey regenerate on their own in clean water. If rotting, increase water changes and reduce food to prevent bacterial infection

Sucked into filter intake

PreventionFit a sponge over the filter intake. Use a heater with a guard and leave no gaps

First aidSwitch off the power, then free the fish gently. For burns or bleeding, rest in a separate container with strong aeration

Atypical mycobacteriosis

RouteThrough cuts on the hands when touching tank water or sick fish

PreventionKeep hands out of the tank when you have a cut. Wash with soap after work

Aeromonas infection

RouteThrough wounds that touch tank water or sick fish

PreventionWear gloves when handling sick fish. See a doctor if a wound becomes red and swollen

Gnathostomiasis

RouteLarvae enter the body when loach is eaten raw (live "dancing" loach)

PreventionNever eat pet or wild fish raw. Cooked only

Salmonellosis

RouteHand to mouth after touching tank water, substrate or equipment

PreventionDo not wash tank equipment in the kitchen. Children must wash hands after tank work

Food

• Sinking tablets or loach food, 1–2 times a day
• Feed after lights-out, only as much as is eaten within a few minutes
• Frozen bloodworms or tubifex as a treat 1–2 times a week

Water

• Dechlorinated tap water. Near-neutral pH 6.5–7.5
• Change 1/3 weekly with water at the same temperature. Never do a full water change

Toys & play

• Fine sand 3–5 cm deep for burrowing
• Hides: clay pipes, terracotta tubes, under driftwood
• Hardy plants such as anacharis (roots are easily uprooted)

Nest, bed & hideout

• Provide at least one hide per fish
• A dark, calm spot by day. Burrowing in the sand is its bed

Bedding & litter

• Fine, rounded sand such as paddy sand or bottom sand
• Coarse gravel and Oiso gravel injure barbels and skin
• Siphon feces out of the substrate with a gravel cleaner at each water change

Cage / housing material

Glass or acrylic tank. A gap-free lid is essential

Size & space

45–60 cm tank for about 5 fish. A water depth of about 20 cm is enough

Layout

• Maximize floor area and place several hides
• Use a low-flow sponge or undergravel filter
• Plug cord and tubing holes with filter wool or covers

Placement notes

• Out of direct sunlight and the summer afternoon sun
• On a stable stand with little footstep vibration

Exercise, free-roam & walks

• No walks needed. Swimming in the tank at night is its exercise
• Do not handle; move it in a container with its water
• If too bright by day, it stays hidden

Temperature & humidity

Temperature15–25°C is ideal. Tolerates 5–28°C, but no sudden changes

HumidityHumidity is irrelevant. A lid prevents evaporation and jumping out

Summer & winter

• Summer: cooling fan and extra aeration to keep below 28°C
• Winter: no heater needed, but keep indoors to prevent freezing. Reduce food

Nail trimming

No nail trimming. Instead, do a weekly water change and substrate cleaning, and squeeze-rinse the filter sponge in tank water

Brushing, skin & coat care

Do not touch the skin. Mucus is a protective layer; even netting causes injury. Scoop with a container, water and all

Other care

Barbels are a health indicator. Short or rotting barbels mean poor water quality. Check lid and cord gaps monthly

Protection from predators

• Weigh down the lid so cats and birds cannot open it
• Large fish and crayfish will prey on loaches if kept together
• Outdoors, net against herons and raccoons

Foreign-body ingestion

May swallow coarse gravel with food and get blocked. Use fine sand only, and leave no net or wool fibers in the tank

Being stepped on

Loaches that jump out are often stepped on in dark rooms. If you find one on the floor, pick it up and return it to the tank before anyone steps on it. Never give up on a fish just because it fell to the floor

Getting pinched

Gets wedged in filter intakes, gaps between heater and glass, and cracks in driftwood. Fit a sponge over the intake and leave no narrow gaps

Falls

Jumping out is most common at night, when startled, or when water quality is poor. Weigh down the lid, keep the water level 5 cm or more below the rim, and rehydrate a dried fish in water

Escape

Escapes through lid gaps, overflows and drains. Search around the tank first; even a dry fish on the floor should go back into water to check for a response

Safe release procedure

1. Stop cohabiting with predatory fish immediately. Scoop the loach with a container
2. If chased by fin-nippers, use a divider or a separate tank
3. If you must hold it, use wet hands, briefly, over the water surface
4. If it thrashes and may fall, bring it close to the water and let it slip off

After the release

Torn fins and barbels regenerate in clean water. If white cotton or red patches appear, isolate and treat as a fish disease

What to tell the vet & what to bring

Water temperature, pH, last water change, food, tank mates, photos of symptoms. Bag the fish in its own tank water. Call ahead to a fish vet or specialist shop

Checking consciousness, breathing & heartbeat

• Are the gill covers moving? (normal is about 60–100 per minute)
• Does it flee when touched or when a light is shone on it?
• Even a dried fish can recover if the skin is moist and the body bends

Stopping bleeding

• Fin and barbel bleeding stops on its own in clean water
• A 0.3–0.5% salt bath protects mucus and prevents infection
• Continued skin bleeding or ulcers: go to a fish vet

Transport

• Bag with tank water and plenty of air, kept in an insulated foam box
• Keep dark and do not shake. In summer, use ice packs to prevent overheating