Fish Disease Diagnosis
Fish Disease Treatments
Ponds, Aquaria & Filtration

Fish health and water quality

"Look after the water and the fish will look after themselves." That just about sums up just how important water quality is to fish health. Indeed, unless conditions are right, fish health problems, disease and fish losses will follow as sure as night follows day.

The birth of water

How water is formed: oh, and by the way, you don't think that rainwater is pure - do you?

Sample downloadFish are open systems

and are thus affected by changes in the surrounding water. Understanding this is fundamental to all aspects of fish health

The unusual character of water

It's strange stuff, but without it there would be no life on Earth and no fish in ponds!

Osmosis and osmoregulation

 are major factors in fish health and easily affected by water quality, stress, and disease.

The final cocktail we call pure water

It is an amazing cocktail that has a major influence on fish health.

Fish are like leaky parcels

of water swimming around in a tank or pond - no wonder water quality is so important to fish health.

Defining water quality

With over 90% of all health problems related to poor conditions do you meet the 5-point standard?


The silent killer always ready to strike


Not quite as dangerous as ammonia, but still a major threat to fish health.


What is it? an important topic that affects virtually every aspect of fish health and water quality.

Water hardness

A major water quality factor that affects fish health, water quality and disease treatments- yet few fish keepers check it!


Has a major influence on all aspects of aquatic health as well as  oxygen levels and fish immune systems.

Water testing

The key to fish health. What and when to test


is very useful to control elevated ammonia levels - but it must be used correctly!

"Koi Health & Disease" by Dr. Erik Johnson DVM is 200+ pages from Fish Health Practice - Readable by Beginners and delivered overnight from

Fish disease problems? Need some help? The help pages take you through the basics of the 'fish health work-up' diagnosis method and basic fish disease treatment methods.

90% of all health problems and fish deaths are caused by poor fish keeping! The key pages are essential reading for all beginners and intermediates who are serious about disease prevention.


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What if you could just get "Here's what to treat with." and no advice or education?

VISIT:  h t t p s : / / f i s h t r e a t m e n t s . c o m

Expanded Content by Dr. Erik Johnson, and Used with Permission; Frank Prince-Iles ©2009 All Rights Reserved