So I bought my 29g biocube used and the lady I bought it from was running a fluval 305 on it. Anyway, I have been way busy lately and haven't had the time to come on here and ask some questions. This has been like three weeks now and the tank is running just fine. Nitrates,nitrites,ammonia is all perfect. This is with the 305. I am thinking about creating a sump out of a 10g that I have lying around. Should I just not mess with it since the 305 is doing fine or should I make a sump? Im just thinking of the saying "dont fix it if it aint broke"... ya I know a sump is better but is it going to screw with my system? I have a F. percula, royal gramma, watchman goby, zenia, torch anemone, candycane and some shrooms. They are all thriving and growing. I just want the best for THIS tank. If its going to be fine with the 305 and regular maintenance of said filter, I am ok with that. I would like a sump thought as I know that it is better for the tank. Inputs?