The diagnosis of your fish health problem is in one of these twenty videos and frankly, honestly? Most people have the problems figured out in the first 5. Because almost ALWAYS it’s a thing with crowding, or water quality, and then a parasite that responds to BSDT.
Professional fish health help video (Click)
Start the Diagnosis Step 1 of Twenty
Diagnose A Fish Disease in 20 Steps Every Time

I did the videos in order of “most common cause of illness” down to video #20 that picks up viruses and further resources. I mean, not EVERYTHING comes from crowding1, water quality of five(2-5) kinds, failure to quarantine(6), seven(7-13) kinds of parasites, their treatment (14-15) fungus (16) bacteria (17) their treatment (18) and viruses (19).
Oh, wait. YES THEY DO. Every time. And that’s what those twenty videos are about.
But, if you’re like almost everyone, and won’t spend time learning and understanding this stuff and just want to fix it without improving as a hobbyist: Just buy these test strips, check your water, bioseed or provide new water, and throw some BSDT into the tank. You’ve got a 80% chance of fixing things.
Diagnose A Fish Disease in 20 Steps Every Time
Here’s a good video to kick off with:
- Handling Stress -Have the fish been handled recently? Why that matters.
- Winter Stress -Temperature. Is it winter? Summer? Why that matters
- Feeding or Underfeeding – Feeding and Underfeeding. Why that matters.
- Ammonia Toxicity -Ammonia and it’s super common, why it matters and what it looks like.
- Nitrite Poisoning -Nitrites and what THAT looks like, why it matters and what to do about it.
- Nitrate Poisoning –NitrAtes – especially common fish killer / weakener in established pond.
- pH Explained -pH is the most common deadly water quality parameter to check. Crash discussed.
- Oxygen Levels – Oxygen levels. Why it might sag, impact of heat and plants, what to do about it.
- Crowding – Crowding. How many is too many. What does that do to fish?
- Still and Stale – Water movement and turnover. Common. Stale, still water. Fish weakener.
- Metabolism – Temperature; it’s influence, it’s pitfalls, the ideals for fish recovery
- Injuries – Cuts and bruises. Is that an ulcer, or a gash? How can you tell. When and if you treat.
- Cleanliness – Cleanliness – Is the pond clean? Properly maintained? Can fish recover in unclean ponds?
- Germs & Microbes – Bacterial infections – a usually unnecessary video because 90% of people have figured out the source of a disease is in their water quality and husbandry. Injections, treatments, etc all discussed.
- Fungus – Fungal infections, you’d be surprised the cause, and the treatment (or lack thereof)
- Bugs & Critters – The Parasites, this is pretty common. What you need to know about them, and their treatment.
- Viruses like KHV – Viral diseases, like Koi Herpes virus and some of the skin-viruses that cause warts.
- Video 18 –> No video 18 lol
- Quarantine – Quarantine. If you did it, then the list gets shorter. If you didn’t do it, (and how to do it) the field remains very wide.
- Further Resources – Resources for more help, diagnostics, fish vets who still do it.
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