False julii corydoras
Corydoras trilineatus
easy careOverview
The false julii corydoras (Corydoras trilineatus), better known as the three-line cory, is one of the most widely sold spotted catfish — and the fish you almost always get when you buy a “julii”. Its silvery body carries a net-like pattern of dark markings and a bold line down each side. It is hardy, peaceful and endlessly busy along the bottom, making it an excellent community catfish for beginners who can meet its simple needs.
Tank & water
A group of six needs at least 60 litres (15 gallons) of floor space. Hold 22–26 °C with a heater and a gentle filter on stable, well-cycled water.
- Smooth substrate: sand or rounded gravel protects their delicate barbels — see best aquarium sand and gravel and the substrate hub.
- Cover: driftwood, caves and planting give security so they forage in the open.
- Stable, mature water: keep nitrate low with routine maintenance.
Feeding
As omnivores, false julii corys forage the substrate all day. Feed sinking pellets, wafers and granules — a good sinking food is essential so it reaches the bottom — with frozen bloodworm or daphnia as treats. Browse our best fish food picks. They are natural scavengers, but never rely on leftovers to feed them; give a dedicated evening ration aimed at the floor so slower foragers get their share.
Tankmates
Peaceful and sociable, false julii corys suit calm communities of tetras, rasboras, dwarf gouramis, bettas and cherry shrimp. They shoal happily alongside other corys such as the bronze, panda or sterbai. Avoid large or boisterous fish that out-compete them at feeding time.
Frequently asked questions
The false julii — three-line cory in all but name — is a beautifully patterned, easygoing catfish. Give it a group of six on smooth sand in stable water and it will forage contentedly for years.
False julii corydoras — frequently asked questions
Is the false julii the same as the julii corydoras?
Not quite. The false julii is Corydoras trilineatus, the three-line cory, which is by far the more common fish in shops. The true Corydoras julii is rarely imported, so most tanks labelled julii actually hold trilineatus. The care is identical either way.
How do I tell the false julii from a true julii?
Look at the pattern. The false julii (trilineatus) shows connected, net-like markings and a bolder line running along the flank, while the true julii has finer, separate spots on the head. Both need the same group, sand and stable water.
Do false julii corydoras need a group?
Yes — keep at least six. They are shoaling catfish that become shy and stressed when kept alone or in twos, but confident and active in a proper group of their own kind.
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