Hello everyone,
I bought a 29 gal Biocube a few months back and I have since realized that this tank has a lot of flaws. The tank didn't have enough flow and the filter was always getting clogged.
The fix, first I bought an Oceanic BioCube protein skimmer and placed it in the 1st chamber; there is hook on the protein skimmer, hang it directly onto the filter in the 1st chamber. The instructions say to remove the filter and replace it with the protein skimmer, but thats an error on Oceanic's part. Make sure the filter is in its tracks.
Second, the water flowing from chamber one to chamber two (middle chamber) hardly has any flow. The channel is not wide enough. I took a saw and cut the rest of the plastic off, creating and wider channel and allowing the water to flow more freely. This helped the water to filter faster and it keeps the water quality cleaner.
Third, make sure that you use Nutri-seawater, it's the best water for your reef. The mixed water from the stores suck. The Nutri-Sea water is cleaner and the coral love it; and you don't have to add additives such as calcium, strontium, iodide, etc, because the water is already balanced with these nutrients.
Fourth, the flow coming out of the pump was not enough to circulate the water around rocks in my tank, so I added a Koralia nano powerhead. This helps circulated more water around your tank, so you don't have any "dead" spots without flow. The powerhead's magnets can actually be installed in the 3rd chamber (use the rear magnet and hold it in the 3rd chamber and place the powerhead in the tank where the water returns to the tank). This will disguise the powerhead on the back wall and it keeps the look of the tank clean and consistent.
Hope this helps all the frustrated Biocubers out there.