I find aquarium's at times do not give my A D D enough stimulus. You should not throw off the balance when the tanks are running perfectly. Growing Algae in the sunlight is something you can play with. Not to much an issue when you do not have filtration or fish. Throwing off the balance is not a problem. Fun trying different things to get good algae growth. Still have not created carpet algae. The green rocks are useful to fry and a river tank. Just rotate the rocks every 2 to 3 weeks. One time I had a Hillstream loach hitch a ride on the rotating rocks. Heaven to a scraper. I like that I can use my out of date fish food for Nitrogen. Put a bit if 20 20 20 in. Flow the water with a wave maker, heat it, and lately I hooked up my CO2. Just enjoy playing with it without having a disaster