Hi everyone, newbie here I have had my 10g up an running for... I would say 6 months now. I got it in one of those complete setup packages. I know that most the bacteria that is created during cycling live in the filter, so am I actually doing more harm than good when I replace the filter cartridge? I was replacing the cartridge on a schedule (about once every 4 or 5 weeks, occasionally longer depending on how well I thought it was working at the time) as per some directions I had read, and didn't think anything of it until I recently saw a post mentioning cutting the cartridge to take the carbon out and then continuing to use the rest of the filter media. So basically, did I fall into another one of those traps to get more money, sort of like how the shampoo bottle tells you to repeat so that you use, and subsequently buy, more shampoo? Or am I really doing alright with replacing the cartridges? Never had a problem with any mini cycles after changing cartridges but I thought I'd get this cleared up. Also as a mini note, I've had some white residue in the filter. Is this something to be concerned about, should I just wipe it off and forget about it, or is it something benefici that I should leave in? Sorry for so many questions. There's so much to learn! TL; DR: Changing filter cartridge regularly: yes/no? Also: white residue inside filter?