How to clean rock background?

[_Matt_]

I bought I rock background about 6th months and have been cleaning it every two months or so. Some of the algae I can’t get off by just using a hose however. Any tips for how to get it off?

 

[Autumnsky]

Is it foam? Maybe a soft bristle new toothbrush little kids if you need to get in tiny spots.

What kind of fish in the tank? Maybe you could get a live cleaner, like a Mystery snail, or a couple Nerite snails? With consideration in what is already living in the tank.

Then there is the lighting as a possible way to reduce algae.

 

[Tony30gal]

I would buy some generic 30ppi foam pad (for ponds and such) and just scrub it manually with your hands! I use this foam for tons of stuff! Here is a link:
https://amzn.to/2Mf6Mj0