justletmein -
Thank you for your quick and quality response. In regards to biological filtration, would the Bak-Pak2's biological filtration capabilities be sufficient enough to remove the Emperor? To my naive eye, it just looks like a bunch of plastic shreddings, which would theoretically give bacteria a place to live, but I question the amount of filtration that could be effectively accomplished. With my canopy, I can only have the Bak-Pak OR the Emperor, not both.

I presume that my 'live sand' is somewhat effective at biological filtration, or am I confused and it's only effective at breaking nitrate into nitrogen bubbles?

Am I correct to guess that my limestone rock is absolutely useless in aiding in biological fitration? Though it's reportedly pourous, I think it probably pales in comparison to the live rock you're talking about.

Another quick question regarding the Bak-Pak2 - Can it accomodate a heater as well, or is that only the Bak-Pak1?

Thanks, doug.