Common Koi Fish Diseases — Identification, Symptoms & Treatment
Understanding koi diseases is crucial for every pond owner. Early identification of symptoms can mean the difference between a minor treatment and losing your fish.
Below you will find detailed information on the most common health conditions affecting koi in South Africa. Each guide covers identification, symptoms, and when to seek professional help.
Parasitic Diseases
Chilodonella
A fast-acting parasite that targets skin and gills, causing a distinctive milky film on the body.
Costia (Ichthyobodo)
An aggressive parasite that can wipe out an entire collection if left untreated.
Trichodina
Disc-shaped parasite linked to poor water quality, causing irritation and flashing.
White Spot (Ich)
Visible white cysts on skin and fins caused by Ichthyophthirius multifiliis.
Velvet (Oodinium)
Causes a dusty, yellowish coating on the skin that gives a velvet-like appearance.
Blood Parasites & External Parasites
Blood & External Parasites
Sleeping Disease (Cryptobia), Gill and Skin Flukes, Fish Louse (Argulus) and Anchor Worm (Lernaea).
Bacterial, Fungal & Viral Infections
Bacterial, Fungal & Viral
Aeromonas, Pseudomonas, Columnaris, Saprolegnia, Branchiomyces, KHV, SVC, Carp Pox, and Lymphocystis.
Concerned About Your Koi?
Early diagnosis is the key to saving your fish. Contact us for a professional on-site health check.