99% of people aim to have no algae but this is incredibly difficult to achieve.
Algae is often caused by an imbalance between lighting, co2 and nutrients. The more algae you have the greater the imbalance in your tank and vice versa.
I do not agree that limiting nutrients is a form of algae prevention. Plants need nutrients to grow, if they dont get the necessary nutrients then they will not grow to their full potential and cannot out compete the algae.
I do agree with regular water changes.
Floating plants can be useful but bare in mind they will shade the plants below them
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