I have a 360g community tank. My wet dry is 60"X20"X20". Stock: leichardti, silver arowana, mbu, flagtail, (5) burundis, (2) emperors cichlids. I have medium size gravel substrate and wood all through the tank. I never clean the gravel and only do 20% water changes twice a week. Am I going to run into problems? Do I need to vacuum the gravel? Its deep and difficult, but I would do it for my pets....