Can anyone help me in biology and ecology measurements?

I am a high school student, and i have an ignment which is to build an aquatic ecosystem. My task is to measure the [CO2],[NH3],[Cl-],[O2],level of algae it will not be difficult if i have one of those test kits, but the problem is that i have to use chemicals and titrations and other techniques (all equipments must from school, so there are no test kits.) since this project is independent, the teacher will not give any advices. So i am wondering if anyone have ideas of how to measure the concentration of [CO2],[NH3],[Cl-],[O2],level of algae in the aquatic ecosystem.