The setup is pretty straightforward. Water from the bathroom sinks and showers goes through a chlorination filter and into a holding tank, where it can be pumped to the toilets. (I'm skipping the washing machine and kitchen sinks, since they require additional filtering and I'll recycle plenty of water from the bathrooms alone.) It's not difficult to DIY, but the central challenge is monitoring and controlling the level of chlorine in the storage tank. Too little, and you'll get bacteria in the tank. Too much, and it will kill the bacteria your septic system needs. So I'm using a new setup from a company called Blue Eco Systems that funnels water through a chlorinator to carefully control how much chlorine goes in. Carbon filters on the overflow and bypass lines prevent chlorine from getting back into the septic tank and the toilets, lest my bathroom smell like a swimming pool.