Select from options: Continue writing the next sentence.

How to decrease aquarium algae naturally
Test your water.
Checking the parameters of your tap water is always a must any time you are having some sort of biological issue with your aquarium. Look for high nitrates, nitrites, and ammonia.

Available choices:
a). Monitor your water while you are testing, and change your filter every couple of months. You can test your water once a month for the moment and then use a small pump to just stream water up the filter to your tank.;
b). If you see rare and interesting substances that are hard to remove, go to an aquarium store to purchase some test water. Many stores contain test water and are offered at a discounted rate.;
c). These will usually be indicators of the cause of your brown algae bloom. Chemicals in the tap water itself, such as phosphates, can also increase algae.;
d). Any nitrates or ammonia that are present in your water should be avoided, since they are highly flammable and might contaminate your water. You can obtain a chemical tap water test kit from an aquarium store.;
Answer:
c).