Just added a third growbed (this one 4 X 8') which doubled my GB capacity. Recent rains have dropped my pH and that, coupled with an increasing fish weight load, has caused a few ammonia spikes. The new GB should alleviate that.

I put together a video - mainly for my non-aquaponics friends who wanted to know more about aquaponics and what I was doing with it. It will be pretty basic for everyone here, but I'll post the link anyhow. I added another pump to my system with this expansion. Yes, I know I could do it all with one pump, but I like having redundancy -especially given our Florida thunderstorms and the frequency of power surges which tend to trip the GFCI built in to one of my pumps. That, coupled with the re-plumbing required made me decide to just add another (third) pump with my GB expansion. I have extra pumps and had enough supplies on hand to add them - but a bigger pump and more PVC to re-plumb everything wasn't something I wanted to tackle right now.

Here's the link: http://www.youtube.com/watch?v=8pOTVqoqZQ0&feature=plcp