Team:UCL Academy/HumanPractice/Activity3

HUMAN PRACTICE ACTIVITIES

Commercial algal growth containment

Algael growth is efficiently limited in commercial environments. Could these approaches apply to individual use, from fishtanks to local ponds? We conducted research on algal growth containment in two different environments - a zebrafish laboratory and a commercial aquarium. 

Visit to the UCL Zebra fish laboratory

The 5000 tanks held at the UCL zebrafish lab all need to be kept free of algal growth. We visited the lab to find out more about their strategy. Tanks are emptied before cleaning as they are each hold about 1.5L only. The fish are fed through a solution that is put into their water rather than by the dry food you commonly purchase at pet stores. A small room next to the fish tanks contains the filtration system, a massive system including a UV chamber and several filters.

This type of cleaning and filtration system is unfeasible on a household or natural lake scale. Therefore, our GMO would prove to be a more viable option for these types of settings.

Meeting at the London Sea Life Aquarium

We arranged a meeting at the London Sea Life Aquarium to investigate how they keep algal growth to a minimum in their tanks.

The main tips are:

Tanks cleaned on the inside everyday to remove any algal growth (whilst the tanks are still full).

ED Lighting rather than metal halide lights, as the latter create a lot of algal growth very quickly.

Regular water changes; around 10 to 20 % of the water is removed and replaced by cleaner water; big water changes are difficult and expensive.

Topped up with cleaned sea water.

Professional salters to create that sea water, as it is artificial.

Carbon filter in the tank which soaks up phosphates.

Additional phosphate remover is often hung in a net bag in the water and replaced every few months.

Denitrification filters grow a special type of bacteria to remove nitrates from the water.

Fish food contains high levels of phosphates and nitrates; usually this isn’t a problem, but if you overfeed the fish too much of the food will rot and add more nitrates to the tank.

This gave us the idea to test algal growth in varying phosphate and nitrate concentrations, leading to our algae experiments.