Practical Fishkeeping Diploma - Week 1, Day 1


Welcome to the first of a five-part series of lessons to guide new aquarists through the basics of fishkeeping.

Week 1, Day 1: Introduction

Each week, over a five-day period, we’ll be taking you through one basic but essential area of the hobby, covering water quality and chemistry, filtering and the nitrogen cycle, fish physiology and habitat, disease management, and aquarium husbandry and management in turn. We’ll post up a new part of each module daily from Monday to Friday, until all five modules are covered.

Each of these areas will be broken down in to key topics, and then stripped back to the bare essentials, giving you the chance to absorb essential, individual points without being overwhelmed. If you’re not academically gifted, do not panic — the course focuses only on the bare basics of fishkeeping, and we promise not to bamboozle you with confusing charts or long, esoteric formulae. For those aquarists wanting more of a challenge, we hope to offer an advanced Diploma later on.

As the course develops, you’ll see that some sections draw upon knowledge covered in previous sections, helping you to build up a comprehensive picture of the interconnected nature of all the different strands of fishkeeping experience.

At the end of the five weeks, you’ll have the opportunity to take a test to see if you qualify for the Practical Fishkeeping Aquarist Diploma. By that point, you’ll have read through and had time to ingest all of the information from the modules — there’ll even be a short ‘practice questionnaire’ to get to grips with before the proper test.

Anyone can take the course — there are no requirements for previous training or experience, although it’ll obviously be a great help if you keep an aquarium of your own.

After successful completion of the test, you’ll receive your formal Aquarist Diploma as a PDF download for you to print off. If you live in the UK and don’t have access to a printer, there’ll be an option to purchase a luxury print version of the Diploma that we can post to you.

This first week, we’ll concentrate on the essential subject of water – how it behaves, what goes in to it, and how it’s properties beyond our immediate senses can impact on fish welfare.

It’s important to note that key points will be highlighted in bold writing — in fact, you might want to write that down in your notebook right now. These are points you need to focus on specifically, as they’ll be highly likely to appear in the final examination.

So, grab a notepad and pencil, grab a hot drink (all the best studying takes place with a cup of tea or coffee) and teach yourself a thing or two about fishkeeping!

In module 1, we shall be learning about Water quality and chemistry.

Understanding water is essential to caring for organisms that live within it. In aquaria, we concern ourselves with five aspects of water.

These are:

Gas content – the likes of oxygen and carbon dioxide, essential for life.

Temperature – incorrect temperatures will cause illness or death.

Chemistry – in the aquarium sense, we use chemistry to refer to pH and hardness of water.

Quality – a measure of the contaminants that could harm aquatic life.

Movement – essential for successful regulation of gases.

Week 1, Day 1: The pH scale

All water has a pH value. This is the measurement used to define whether water is acidic, neutral or alkaline (sometimes called basic) in nature. Different fish have different preferences for pH value, so matching the pH to the fish you keep is important.

The pH scale runs from 0 through to 14. When the ions that cause water to be acidic or alkaline are perfectly balanced, then the pH value will show to be 7.0pH. As the ions that make water acidic dominate, the scale will drop below 7.0pH. Conversely, when the ions that make water alkaline dominate, the pH will rise above 7.0pH.

The pH scale is logarithmic. That is to say that a pH value at 6.0 is ten times more acidic than a pH of 7.0. A pH value of 5.0 is ten times more acidic than a pH of 6.0, which makes it 100 times more acidic than a pH of 7.0. (this continues down the line, so a pH of 4.0 would be 1000 times more acidic than pH 7.0, and so on).

An incorrect pH value will harm fish, as will a fluctuating pH. Any shift of more than 0.5pH over a 24-hour period can be detrimental.

Other aspects of aquarium life can affect pH values. Typical examples of these include:

Biological filtration – this produces acids that slowly lower pH.

Carbon dioxide – respiration of plants and fish, as well as carbon dioxide dosing for plants, can drastically lower pH.

Wood – can release acids in to the water.

Rocks and substrate – those containing calcium carbonate can cause an increase in water hardness, and subsequently pH.  Synthetic and resin ornaments typically will not affect pH.

Click here for next lesson: Water hardness

How to gain your diploma: Once all the course modules and revision pages have all been posted online, we will open a link to a website that allows you to take your free online exam. If you pass the exam, you will digitally receive your very own Fishkeeping Diploma, to show that you have successfully completed the course, and which is yours to display on the wall near your aquarium, hang in your fish house — or keep somewhere safe where you can take it out and just look at it from time to time.

Note: The Fishkeeping Diploma is not a formal or accredited qualification and should not be confused with the type of diploma presented by colleges, universities and other educational establishments.

Further reading from our sponsors

Treating common aquarium problems 

Routine aquarium care

Troubleshooting for green cloudy water