I thought i should update on the Fluval g3 now that im a few weeks in. I had to change the mechanical filter twice already. I started with the fine and now run the regular one. after 6 days the fine filter was clogged. Almost no water could pass. This other filter went 9 days without showing any resistance. I cleaned it just because its so easy. the filters themselves are a pita to clean and are expensive to replace. Im happy with a little extra elbow grease. I added a ball valve to the return to adjust it down a bit. The microbubbles have completely dissipated unless you change the filters out. I rock it back and forth to free any air left inside. Its still super quiet and i love the notifications. helps me keep on schedule. Overall i feel that they have been out for a while and people who own them love em. nah sayers who support eheim seem to be a bit short sided simply because of price. Ive maintained several pond canisters and an Eheim on my 55 fresh years ago. Not to say its not they are not beast of filter, but i hated undoing it and taking it outside to rinse every month. Its too easy to just twist and pull up the filter cartridges. No water on floor. I don't really use the conductivity often. i glance at it to see if anything has changed but it only rises if i stir up sand or feed with cyclopseez. Otherwise, i wish this filter had a built in heater. That would simply put it over the top. Do you guys think i could run gfo and carbon or is this guy a bit too small. I guess i could try, but im afraid the gfo will solidify or carbon could deteriorate. you cant see if the stuff is tumbling or not. its a shot in the dark imo.