Hey OP. Sound advice thus far. If I can throw my .02 I would recommend going to sumps. You can do it cheaply by DIYing it all, or you can go expensive and purchase ready to go overflows and sumps. For a sump all you need is a 20g or bigger (depends on your stand space), a pump (I would recommend two for safety), an overflow (two small or one big), filter socks (I just purchased 10 for $43 to my door), and some media (ceramic rings are the most common.) Another kick is that the filter socks only need to be changed every 3-7 days depending on how messy your tank is and the socks are reusable! When you put your last sock in the sump, throw all your used socks in the washing machine (There are many ways to clean them.) No more filter cartridges to replace!!!! The sump media itself, if you mechanically filter very well, only needs to be overhauled like every 4-6 months or so! My old Fluval canisters would go three months and then the prefilters would clog causing the need to clean the whole thing out. Anywho.... my .02 Good luck!