I currently have a 20 gallon long tank with a tetra 20 gallon pump running. I have wood with anubias growing on it, no gravel or any other type of substrate, 6 frogs, and 3 amano shrimp. I also have a screen top with a 15 watt hood light on top of the screen. I leave that on for about 8 hours and turn it off. I feed them 3 times a week. I have no substrate, as I have said, and now I see a tint of green algae growing on the bottom of the tank and I wipe the sides of the tank and see a small amount of algae on the cloth. Would it be best to put some sort of substrate in the tank? Should I put some live or silk plants in the tank? Like I said I have lots of hiding places for them and on my wood I have anubias and java moss growing. I haven't lost any frogs, they are active, and eating. I am just doing a lot of maintenance on the tank since I have a bare bottom. I would like some input to how much better I can make the tank so I am not in the tank 2-4 times a week cleaning it up and controlling the growth of green algae.