Let's talk about how to keep a fish tank clean. There lot's of reasons a fish tank can become dirty. In this instance, it's from algae formation and algae formation can occur due to overfeeding or dirty filters and things like that, or the lack of an algae eater. In that instance, good cleaning and adding an algae eater like a Pacostamus in there is a good idea. However, fish tanks can become dirty for other reasons, and so just make sure you talk to your local fish store. You can take a water sample in and have them test it or you can use a test kit that test pH, ammonia, nitrate, nitrate, nitrites and that might help diagnose the problem as well. But, in overall aquarium sense, they become dirty mainly due to algae buildup and and so you can use a gravel vacuum which would go into the tank and literally suck up the gravel and let it fall back down and that water, that algae or dirty water's going to come out. Also, of course, fish tanks get dirty because all the fecal material that that that the fish produce. So cleaning the sides of the tanks, there are multiple sponges and and and different things that you can use to clean the sides of the tank on the inside and very importantly, making sure that the power filters are clean and that those filters don't need to be replaced from time to time. So cleaning that tank routinely is going to keep it clean and those fish healthy for a long time.