Can Koi Scale Protrusion Disease Heal on Its Own? Teach You How to Tell If a Koi Is Pregnant

Many people keep koi at home, since koi are not only very beautiful in appearance, but also carry good meanings. Scale protrusion is a common koi disease that can occur throughout the year except in summer. If not treated in time, it will affect their ornamental value. So what should you do if your koi at home gets scale protrusion disease? And how do we tell whether a koi at home is pregnant?

Can Koi Scale Protrusion Disease Heal on Its Own?

1. No, it cannot. Scale protrusion disease (commonly known as pinecone scale), is the most hated and most vicious fish disease, and the one that develops fastest. The time from discovery to complete death is very short, so treatment must be timely.

2. Soak the whole diseased fish in a diluted potassium permanganate solution. Getting the concentration of potassium permanganate right is very important; it must never be too strong, because potassium permanganate is a strong oxidant and can harm the gills and internal organs of koi, so it is generally not used unless absolutely necessary. You must add it little by little (use a small measuring spoon), stir it evenly, and then decide based on the situation whether more needs to be added. Once the water turns a faint light purple, that is enough. Then place the fish in it for one minute, which is sufficient. Once a day for three days.

How to Tell If a Koi Is Pregnant

1. Koi do not get pregnant. Even overeating can make the belly look big. Koi are egg-laying fish that fertilize externally; they do not directly give birth to fry, they only lay eggs, and the eggs they lay are unfertilized. Only if a male fish wants to become a father and fertilizes the eggs can fry hatch out. Unfertilized fish eggs are just like the chicken eggs we normally eat, with no life inside. Just as a hen that lays eggs does not get pregnant, a female koi does not get pregnant either.

2. Fish of 5-6cm generally do not carry eggs. If it is not a “stunted old fish”, the fish may have a problem with its internal organs. Generally speaking, koi only start carrying eggs after 2 years of age, and some fish only carry eggs at 3 years of age. Even when kept in a fish tank, a 2-year-old fish should be over 20cm, and usually a 2-year-old fish can reach a body length of at least around 40cm.

3. When koi carry eggs, it is usually at a water temperature of around 20 degrees, and the obvious sign is that the belly is bigger than usual. The spawning time is usually May and June each year, and after spawning there will be yellow or white eggs stuck to the tank wall.

How to Tell Male and Female Koi Apart

1. Generally, on close inspection, the female fish has a shorter and fuller body, while the male fish has a more slender and elongated body. Look at the abdomen: the female's abdomen is relatively swollen and large, while the male's abdomen is relatively wide and also short. As for the female fish, the female's head is slightly narrow and longer, while the male's forehead is slightly protruding; this point requires careful observation.

2. Next is the pectoral fin part of the koi. The tip of the female's pectoral fin is round, while the tip of the male's pectoral fin is slightly pointed. Then comes the breeding season. During the reproductive season, the difference between female and male fish is even more obvious: the first fin ray of the male's pectoral fin and the gill cover develop several small white rough protrusions, called “nuptial tubercles”.

3. After the reproductive season, the nuptial tubercles disappear on their own. The male's genital pore is small and sunken, and gentle pressure with the hand causes milky white semen to flow out; the female's genital pore is slightly wider and flatter, slightly protruding outward, and gentle pressure on the abdomen causes egg grains to be released.

How to Keep Koi

1. Generally speaking, in nature there are several water sources available for us to choose from when keeping koi: rainwater, river water, lake water, well water, groundwater, and tap water.

2. Rainwater has a high oxygen content, but because the air is now seriously polluted, the air contains many harmful pollutants such as car exhaust and various polluting substances discharged by factories and power plants. As rainwater falls, it dissolves these harmful substances into itself, so using rainwater is very risky. It will damage the fish's respiratory system and prevent normal growth and development, so it is best not to use rainwater to keep fish.

From the above, we can know that if a koi is pregnant, the obvious sign is that the belly is bigger than usual. The spawning time of koi is usually May and June each year, and after spawning there will be yellow or white eggs stuck to the tank wall. That is all for today. I hope these little tips I have shared can help you.