Fish Health - Microscopes

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Aeromonas Hydrophila
Ammonia Test Errors
Anchor Worm
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Costia (killer)
Common Myths
(Egg Compaction)

Fat Fish
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Microscope page
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My Fish Jumped
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White Spot

MicroscopeTo be able to check your fish, you should have a microscope or access to one. These photos may help you to identify some common parasites

There are many more such as Ichthyobodo a cool water parasite. We could fill pages on this site with them.

Remember they are caused by stress, including the dreaded water temp 52-56F, water sediments and water quality.

White SpotWhite spot full blown

If you see this amount under your scope take action at once . This is a purely a stress related injection. White Spot has no qualms about killing every fish you have. White Spot can be killed also by warm water but not many of our ponds reach 88F in our summers.

See our White Spot page in the Health section of this site.

leechleechFish Leech

See our Fish leech page in the Health section of this site.

DactylogyrusDactylogyrus (gill fluke)

Dactylogyrus need a temperature of 65F plus is an egg layer so treatment is based over 28 Days. Then Re-Check symptoms high gill rate, scratching.

It has always been thought that this is a warm weather infection. This is not so, the adult will start laying 2 eggs a day at as low as 12oc and many more as water warms. So if your koi have been scraped for childonella, whit spot and costia and nothing found, but the fish still scratch, their gill covers on pond sides and bottom and hang around the filter outlets, then check for gill fluke - as early as February if the climate is mild.

Dactylogyrus Dactylogyrus

Oodinium Oodinium Pillilarus - Velvet Disease

Oodinium not a true parasite is more plant cells known as Velvet Fish has a (Brown - Yellow) dust over the dorsal area.
IchthyophthiriusIchthyophthirius - a swarm spore, also known as asymptornatic spore

Ichthyophthirius (White Spot) a most under rated killer in Koi do not look for white spot on the Fishes Body its mainly in the Gills. Jumping Koi don't jump through pleasure, they jump to rid themselves of the itching, scratching, scales missing & clamed fins

TrichodinaTrichodina spp. (stained)

Trichodina symptom a greyish slime appears over the fishes surface, flicking fins, scratching, clamped fins, laying on the bottom & off there food

I can now confirm that Japanese Trichodina is salt resistant even at 6% and I suspect may be at 9%.
Trichodina Trichodina Trichodina
slime disease - bacterial infectionThis is what's known as slime disease or white coating.

It's just like the fish has been dipped into very weak wallpaper paste. The fish has lost its lustre and they are often flicking against the side and bottom of pond or laying on the bottom with fins clamped to there side.. (If it was white spot they would be jumping). They will also show these symptoms with a high NITRITE reading.

When doing a microscope scrape use 40-100x
If you suspect costia use 400x

ChildonellaChildonella spp. (stained)

Childonella symptoms are as above, but can be a problem in cooler water.
Childonella Childonella Childonella

Columnaris tail rot
Run to end of your cover glass to look for this disease, it shuns the light, moving like shimmering worms on the edge of your scrape or fish tissue. You will need a magnification of around 400 X or better in a saline mount - make saline 6gm pure salt to 100ml pure water.

See our Columnarist page in the Health section of this site.

Body/Skin flukeBody / Skin fluke

Body Fluke is a live bearer giving birth to live young does a lot of damage in ponds mainly in the spring time, if left unchecked will kill fish through secondary infections through the damage they have done through scratching.

Body/Skin flukeDamage that a fish can do to its self from scratching from a body fluke infection.
In the three photos below, the wounds are the result of the fish scratching or flicking on rough objects because it has infections of a parasite and body fluke.

Objects used by the fish include copping stones at water level, planting baskets and unprotected jubilee clips just to name a few. The infection, which has gained entry via these wounds, is aeromonas hydrophiller. This is a soil bacteria which is present in all bodies of water.

80% of all fish ulcers are brought about as result of a secondary infection of aeromonas following a fluke or parasite attack.


Fish LouseFish LouseFish louse

Fish louse symptom looks like a small transparent bead on the fish mainly on fin near the head the pectorals. must be dealt with without delay. This is becoming a real problem now - new cases this year up by 60%.
Anchor WormAnchor Worm (Lernea)

Lernea, which looks like white cord coming from fishes fins or body, can be removed by hand with care. You must remove all the lernea egg case and treat the pond or tank as for argulus.

Check your filters with microscreen for lernea nymphs and other stages of lernea life cycle.

This infection, even when treated on time and correctly, can scar a well prized fish, and ulcers can result from a lernea infection.Lernea

See our Anchor Worm page in the Health section of this site.