More details I guess will help.
I have a 28 gal nano cube, currently has 20 lb of sand 30 lb of live rock. I have a Royal Gamma and a Shrimp Goby Barbershop as occupants.
The cleaning crew consists of 2 Mexican turbo, 4 Florida turbo, 5 Nassariusl snails, 20 blue leg hermits, and 3 jade hermits and a lettuce nudibranch.
My coral in this tank is a small cluster of orange Ricordea, Green Star Polyp (growing nicely up the side of the tank) and a brain coral open red.
My problem is I have had a serious growth of green algae and purple scales that grow on the glass, and red slime that has been growing in the corner under the water outlet. I have been pulling the green algae out by hand and scrapping the scales from the glass and sucking out the red slime but in a few days everything is right back to where it was.
A couple of days ago I followed some advise and removed the blue filter sponges and cleaned them stirred the sand and then did a 5 gal water change (I normally only do about 2 gals once a month tank is 11 months old) Now the green algae has reduced but is still there, I have noticed that caulerpa was growing in the rocks under the green algae and now the red slime has moved to the whole bottom of the tank. I keep moving the sand around to remove the red slime but it just keeps come back.
The water I use is tap water but is filtered.
I have already tried the red slime remove keeps coming back.
I am starting to think too much boi mass might be the problem. I have everything that came with the Nano cube in use and have not cleaned it because I did not want to interupt the balance of the eco system. but am currently open to suggestions.
I have added a small protein skimmer.