Breeding / Egg scatterers
Egg scatterers · Moderate

Breeding the adolf's cory

Spawns like most corys: with about two males per female, a large (50-70%) cooler water change once females are full of eggs triggers spawning; eggs go mainly on the glass. Fry are not easy to raise and need excellent water quality.

Step by step

Pairing

Keep a group with more males than females; condition with live and frozen foods. Males chase females in a 'T-position' before spawning.

Breeding tank

40 L tank with a sponge filter, fine sand and java moss or spawning mops; a cool water change is often what sets them off.

What starts it

A large cool (3-5 C) water change, lower barometric pressure feel, and heavy feeding of live foods.

Eggs and young

Sticky eggs placed mainly on the glass (or fine plants/mops); they hatch in 3-4 days and breeders add methylene blue or alder cones to stop fungus.

Raising the fry

Move eggs to a hatching tub with an air stone and a pinch of methylene blue or alder cone. Feed microworms and newly hatched brine shrimp; keep water spotless.

Common mistakes
  • Dirty sand that causes barbel erosion
  • Not removing eggs from hungry adults
  • Skipping the cool water change trigger

Male or female

Females grow larger and, when mature, are noticeably rounder and broader-bodied than males, especially when full of eggs; easiest to see from above.

Can I breed it in my tank?

  • Use a separate small tank with a sponge filter and spawning mops, so the eggs aren't eaten.
  • Takes some experience.

Day-by-day plan

Typical for egg scatterers

  1. 14 days beforeCondition the parents

    Feed live or frozen food twice a day. Keep males and females apart if you can.

  2. Day 0Spawning

    Eggs are scattered over mops or fine plants, often at first light. Remove the parents straight after.

  3. Day 1Eggs hatch

    Most eggs hatch in 1–2 days. Keep the tank dim and remove white (fungused) eggs.

  4. Day 4Free swimming, first food

    Fry use up the yolk and start swimming. Feed infusoria or liquid fry food several times a day.

  5. Day 8Baby brine shrimp

    Switch to newly hatched brine shrimp or microworms. Start small, daily water changes.

  6. Day 21Crushed flake

    Add finely crushed flake. Sort fry by size so the big ones don't eat the small ones.

  7. Day 60Ready to move

    Most small fish reach about 2 cm in 2–3 months and can join the main tank.

A general guide for this breeding type. Days change with temperature and species.

Simulator: guided

Stage 1 of 7Condition the parents

Feed live or frozen food twice a day. Keep males and females apart if you can.

Simulator: try it yourself

Set up a virtual breeding tank and see what would likely happen.

No spawning
  • Without live or frozen food the parents aren't in breeding condition.
  • Corydoras usually need a big, cooler water change (like rain) to start spawning.

An educational estimate from the breeding rules, not a promise.