I have a 55 gallon with 14 african cichlids all under 2 inches. The tank is cycled and healthy. Ph is around 7.8 and there is no obvious ammonia in the water. Yet for some reason there was a little algea bloom about 2 weeks ago and i did a few 50% water changes which helped a little. The water is no longer hard to see through, but it isnt "clear". I was wondering if i should cover the tank with a black sheet and cut off all light to the aquarium to kill the algea. or should i use a chemical supliment? and should i keep doing big water changes? what do you guys think?