How I got into the water testing business by Tim Apps.

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I remember when I was pretty small, standing at the bathroom sink running water from the tap and running my fingers through the cold water. I tried to figure out what water was but at that time could only come to the conclusion that "water was water" and there was "nothing simpler" and "nothing the same as it". That's exactly as I recall it and is a good example of how we form mental models to explain something.

Ever since Grade 5 I wanted to be a scientist. It has been a long and interesting journey.

I did science at Monash University in the late sixties and benefited from some very enthusiatic lecturers and tutors. I was lucky enough to learn about limnology under Bill Williams and Ian Bayly. Interestingly while recently building up a suite of water tests I had to refer back to my field notes in limnology (lucky I kept them for about 30 years).

I was a science / maths teacher in High School for a while then joined Fisheries and Wildlife in Victoria. I was involved in wildlife surveys all over Victoria - this is where I started to take notice of aquatic habitats. Later I was involved in some fisheries management projects including a taste of research in aquaculture.

I spent several years as a computing / IT teacher at TAFE, and more recently teaching horticulture. A few years after graduating I went back to do a 4th year Botany / MSc prelim. My project was working out the mineralisation rate in a cleared paddock and in an adjacent forest soil. Soils are very interesting, mainly because they are so complicated and because we know very little about how they actually work (we know a lot of factual information).

I nearly forgot - I had a small wholesale plant nursery for a few years. This is where I got my hands dirty (very dirty sometimes) and started to realise that when it comes to solving plant growth problems we had very few tools available.

A few years ago I did a masters degree in education because it seemed to me there was a lot to be gained by taking typical 'factual' knowledge and organising it help students build a deeper understanding.

My PhD was in a field which could be described as a cross between cognitive science, computer science, education and aquatic science. The focus was on integrating scientific knowledge with problem solving knowledge and demonstrating this in a practical way by building a problem solving strategy applicable to water quality problems.

Specifically the focus was on diagnosing acid - base disturbances in water (this applies to the soil solution as well). I adopted approaches used to understand diseases through analysing pH disturbances in the blood. It is based on an idea that pH is mostly regulated by the CO2 / bicarbonate equilibrium reaction. Acidity and pH affects and is effected by other factors and is extremely important in biological processes. That's why the focus here is acid - base disturbances.

Because there are some inbuilt delays in this reaction a disturbance which effects say CO2 or acid input will result in an equilibrium "imbalance" if that makes sense. If CO2, bicarbonate and pH are measured then we can do a calculation which shows for example how much the measured pH differs from that theoretically expected. Not only that but we can tell which direction the disturbance is coming from. Then for a given situation, we can look for likely causes for a problem. Paradoxically some of the greatest advances can come from applying simple ideas. For example most of my interpretations are based on what I call "high school chemistry". Things change when you start to ask questions like "How do chemical equilibria work, what do they mean and how can they be applied to real problems?" Results have been encouraging so far. For example in a farm dam that I have vistited a few times I've found that when the dam floods the measured pH change probably results from a combination of influences. In this case from lowered CO2 and from increased H+ input. Now the question is why have these factors changed and what are the consequences. An important result is that by using a chemical equilibrium model we have uncovered two primary disturbances to the pH buffering system. They act together and at least partly compensate each other. There are also inbuilt compensating reactions which try to keep the pH stable. Part of this type of research is simply establishing that the approach itself is reasonable or appropriate!

I graduated in October 2007 with a PhD from Monash University. The title of the thesis was "Model based diagnosis of acid-base disturbances in natural waters". The Thesis summary is: Understanding the causes of water quality problems is difficult because of the large number of factors involved. This thesis shows how an analysis of the acidity regulation system can provide the starting points for a diagnosis. Applications are in water management and water treatments and more broadly in environmental education.

Tim taking a water sample.

I started Apps Laboratories in 2002 and set up a lab at Gembrook. We carry out water tests and some soil tests and also supply water and soil testing products and water filters. Currently I'm combining water testing in the lab with working with clients on projects such as water treatment, waste management and water recycling, supplying and supporting use of water and soil test equipment and, looking to the future, knowledge-based android app development. This is a good balance as each area supports the others.

Now for something completely different. In 2015 our family bought a dairy farm in South Gippsland. Farming is both interesting and challenging because of the complex decision making required at every step. We are setting up a propagation and nursery area to grow plants for alternative crops, fodder trees for the cows and for replanting some native vegetation in the eroded creeks and gullies.


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