Originally Posted by xrayjeeper83
Yes there is a light, not sure what kind or wattage and what not. It came with the tank and doesnt say on the housing. Its in a power compact housing if that helps. It has two bulbs inside but only one works. Its also has a "moon light" that is on when the regular light is not. The light is on12-14 hours a day. I get up at 10ish and turn it on and it goes off at 2am when i go to bed.
No I have no live plants, cichlid tank. Looking at that site Im not really sure what kind of algae, it comes off really easy, but kinda looks like that spot algae.
Didnt have any problems with algae with my common pleaco.
This is quite straightforward. You have light plus nutrients, and with no live plants, algae will appear and use the nutrients in the presence of the light and multiply. Your pleco appears to have been keeping it under control. All sounds perfectly normal and natural.
A good algae fish that will survive with your cichlids would probably handle things, one of the small plecos. Also, reducing the light significantly would help; without plants the only reason for a light is for you to observe the fish, as fish don't need light per say. I would also eliminate the moon light at night. Fish (and plants if you had them) need a period of total darkness. Ten hours is suggested.
And a comment on partial water changes, as noted in subsequent posts, these should be every week, with 40-50% changed. As someone mentioned, nitrates themselves do not cause algae, but they are indicative of what does--nutrients. A weekly pwc will help handle this by reducing nitrates which means reducing some of the nutrients the algae needs. It is also healthier for the fish. There is an excellent article on this in the November issue of TFH. The toxins that rapidly accumulate in an aquarium, especially with larger fish, cannot be removed by any filter, only a pwc can do this. A significant weekly pwc is the best thing an aquarist can do for any aquarium without plants.