Decaying Algae is Bad, Living Algae is Good!
Algae may not be the prettiest thing to look at in your tank, but please restrain yourself from rushing to use chemical treatments to eliminate it. When you think about it, as long as the algae is alive, it is acting as a natural filtration system for nitrates and phosphates. Algae only really begins to harm your tank once it starts to decay and lower the tank’s dissolved oxygen levels. So really you want to avoid the decomposing of the algae. Periodically siphon algae off the rocks or scrape the glass and let the filter take care of the floating pieces from your scraping. This way, you are removing the algae along with the phosphates and nitrates that the algae has absorbed from the system.
Problems with Introducing a Large Cleanup Crew
Other ways to keep different types of algae at bay is to invest in a cleanup crew. Certain tangs and hermit crabs will eat specific algae such as bubble or hair algae. Keep in mind though that the hermit crabs produce waste and who is there to clean up after the cleanup crew? If you introduce even just 10 hermit crabs (a relatively small number compared to what others may recommend) the hermit crab waste will shortly become very noticeable and you will notice an increase in detritus build up. Hermit crabs are pretty effective at eliminating hair algae in just a few weeks so it may be worth it to keep around 10 and just live with the tradeoff of extra detritus build up.