Koi Filtration - Bead
With a little bit of management every week or so, you can have gin clear water in your koi or fish pond. Bead filtration is more than ten years old and defines the state of the art in Koi and pond fish ponds.

Koi Filtration - Natural
Requiring no weekly management but one big yearly overhaul, natural filtration is the easiest there is. Relying on live plants and organic processes, water quality is usually superb. Described and common mistakes illustrated, visit this site!

Koi Food & Feeding
What should you feed your koi? How many times per day? Is Corn really that bad in a Koi diet? What are the most common feeding mistakes people make? What's the best food?

Koi and Pond Hard Goods
So many places these days, are pure ripoffs. Finding a reputable dealer of koi and pond hard goods isn't as easy as you would think but there's ways to tell. The product line should be to-the-point and not contain shams. Who's doing it right? Visit this site!

Finding Reputable Dealers
The fish are only as good as the dealer holding them. Quarantines, guarantees and fish quality all factor in. What to ask, what to see and how to handle your new fish.

Books on Koi Diseases
You will be introduced to Dr Johnson's Koi Health book but also to other books he's reviewed.

Help With Koi Problems
Koi Community rates a variety of forums and message boards on ease of use, friendliness and quality of help. Not all boards are created equal. Not mincing words here.

Using the above search box allows you to search every site in the DrJohnson network. I'd call that a fishlibrary, wouldn't you?



What Does Crowding Actually “Do” To Fish?

 Crowding can do two things to fish:

  • It can slow the fishes growth and causes stress.
  • It can facilitate the explosive spread of diseases among fish.

 I always visualize crowded fish ponds like big barns full of very dry hay. One little match, and the results are explosive. A warm pond overcrowded with fish is a powder keg if Chilodonella got in there on a new fish. In crowded ponds, if the filter or circulator were to fail, dissolved oxygen depletion is also a danger. 

 As far as stress and stunted growth, the reasons behind this are unclear. Do the fish “feel” stressed by the crowding? Or is the accumulation of yet unknown or immeasurable toxins or biological metabolites the cause of this phenomenon? Since frequent major water changes COMPENSATE and correct the deleterious effects of crowding, I would have to subscribe to the second concept.

 To recap: One inch of fish per ten gallons of water unless the pond is to be “natural” with minimal water movement or filtration, then stock one inch of fish per forty gallons of water.

Koivet.com
Koivet is a venerable, long lived koi and pond fish health site started by Dr Erik Johnson in 1994 as an off shoot of his first few websites at Mindspring.com. Now Koivet is full of information and movies and more.

Koi Beginner
Once you've leapfrogged through this tutorial you will have a solid, working concept of the Koi hobby and what it's all about. This is done just about exclusively with video and very little written material.

DrJohnson.com
More than koi health, this site spans all things animal, by a real veterinarian who shoots you straight.

Fishdoc.co.uk
By Frank Prince-Iles. A UK authority who put this site together some time ago and which is still relied upon as a major source of good Koi and pond fish information

Fish Medicines
Learn about fish medicines, what they do, and where to get them.

PondCrisis.com
If you have a koi, pond or fish problem, this site takes you through twenty easy questions and at the end you know what you need to fix in your pond to create restored Koi health.

KoiCrisis.com
Koi Crisis has a symptoms chart by system you can choose the symptom by fish part, and resolve a lot of Koi pond fish problems or at least, learn about them understand how to remedy them.

Buying Domestic Koi
What does "Domestic" koi mean? Why would you buy that kind? How do you pick good and healthy ones? Who sells them and where do you find the best ones?

Buying Imported Koi
A Japanese or Israeli imported Koi is a beautiful thing. Why would you buy one of those? How do you identify a "good one"? And what kinds are there? Who would you buy one from?