just thought i would share this link I found. check out this guy's wet/dry system. kind of excesive if you ask me for the size tank he has. pretty amazing though.
What a stupid thing to do! A standard tank filled with gravel and rock would do the same thing AND eliminate nitrates as well. Bio-balls were great in the 80's, but we have learned a lot since then!
I have 20,000 gallons of water in my shop, and that is about half of the filtration I have. I just hope they have a prett good dehumidifying system or they are going to have some serious mold and moisture issues. I have a hard time dealing with it in 10,000 sq feet. I doubt their house is that big.