Unit 1: Water Systems on Earth's Surface (revised 2012)

Learn how you can write and reveal secret messages in this hands-on chemistry activity.

Learn how to make a pH indicator and test water samples.

Aquaculture is seen as a sustainable way to produce fish. But are farmed salmon better than wild fish?

4 images of some fish such as koi that live in freshwater river and lake environments and in freshwater aquariums and garden ponds

14 images of some fish such as lion fish, grouper and sharks that live in saltwater environments like oceans, saltwater lakes and aquariums

When fertilizers from agriculture get into lakes and rivers, big problems can result for aquatic ecosystems, food chains & webs!