To understand and control algae in your aquarium

The small green dots you can see on the aquarium glass are actually calcium secreting diatoms  from which the algae grows this is why they are are hard to remove. 
 

Some times an out break of cyanobacteria  can happen especially in a well lit aquarium which is cleaned regualry, it grows faster than algae  and can be a problem controlling, but easy to remove.Cyanobacteria can be red,green, blue or black and thrives where there are high levels of phosphates. It can occur in marine or freshwater set ups, various chemicals can be used to inhibit the growth.
 

Green and brown algae is a natural occurence in any body of water, pond or aquarium, it is a very basic and simple form of plant life that requires the same nutrients as higher level plant life, the more competition for nutrients reduces algal growth.A clean aquarium where all algae is removed will infact produce a more rapid growth than for example leaving some algal growth untouched, very often allowing some algal growth on the back of an aquarium or on some rocks will slow down new growth as the nutrients are being absorbed continuously.
 

Some fish in a marine aquarium such as tangs and surgeons  will perhaps peck at the algae, some of the invertebrates will do so also , cowie snails are a fairly good algae consumer but none of these natural algae eaters will eliminate algae, same as fresh water aquariums, various fish such as plecostomaus,ottocinclus will help remove some algae, usually snails end up being a bigger problem than the algae itself. In freshwater aquariums a healthy plant growth will deplete algae dependent nutrients as in a marine aquarium, growing caulerpa and photosynthetic corals and anemones will also have the same effect.
 

Algal blooms, ultra violet sterilisation is mentioned in the article on koi carp.
 

A dead fish or decaying plant matter will provide nutrients and also ammonia spikes, seneye, pond, home and reef protect your fish.

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