Hi, I have a 10g tank with 4 black neon tetras in it, hopefully 6 tonight and some shrimp (hoping to get them this afternoon.) I have an Aqua Clear 150/30 filter, my tank has been going for a month now. I don't know my PH or anything, if its needed. But is the carbon needed? I was told no, it wasn't, but I want to make sure my fish stay healthy. Thanks!