In some rice-growing parts of the world, farmers use a combination of paddy fields and a fish farm. Rice paddy fields are flooded for much of the growing cycle and water running off the fields flows through pens where fish are raised. Nitrogen-based fertilisers are generally very soluble in water. Which problems could result from farmers applying excess nitrogen-based fertilisers to their paddy fields? 1 decreased fish production in the fish pens 2 decreased levels of oxygen in the water 3 increased growth of algae in the fish pens