1. Short grain or sushi rice are the closest types of rice to Japanese rice. You could use medium grain but long grain or any other rice grains are not suitable. I buy Japanese short grain rice called ‘Koshihikari’ (こしひかりorコシヒカリ). I like it because the cooked rice is fluffier and shinier than other types. In Australia, you can buy Koshihikari at most Asian grocery shops and definitely at Japanese grocery shops.
2. The amount of water required depends on your preference of the cooked rice (al dente vs soft), age of the rice grain (new rice needs less water), and the pot you use (more steam evaporates with a wider pot). You will need to experiment and work out the exact amount to suit you.
3. This is a traditional way of cooking fluffy rice. You will see that each grain becomes white after absorbing water. If you don’t have time to soak the rice in the water, you can cook it straight away in which case you might need to increase amount of water slightly when cooking the rice.
4. Leftover rice can be kept in the fridge for few days or in the freezer. Use the microwave to thaw and re-heat.