No major system problems lately although I did have the solenoid valve on my reactor CO2 get stuck closed (likely after a power outage) which threw off my numbers by the time I caught it and may have taken out a colony or two. Just the other morning, I awoke to the sound of running water - not the open faucet kind but the water pouring on the floor kind. A loose lettuce clip that was in my overflow had gotten caught and sucked into the durso. Fortunately, I think I only dumped around 5 gallons over the top before noticing. I also have a now-beyond-budding aptasia issue. There's really no easy way through that especially when the colonies are so large I can't even clean the glass on the bottom half of the tank. I'm going to try to beat them back as I frag things down to more manageable sizes but you can never get them all - sucks, but it's better than AEFW.
I shot some cascade-style sump plumbing tips to Cjtabares and figure I throw them here also for info's sake:
1 - Oversize your drains. I assume you are going to bulkhead out from the side of one tank then into the top of the next. I think I used 1.5" plumbing for that and they barely keep up with the flow. When a screen is added to the tank side of the drain bulkhead, it gets even worse. The fuge tank which has the screen runs with the water level a bit higher than I wanted. The drain inlet is totally submerged on that one so there's no margin if the screen starts to get covered.
2 - Consider how close you put your drain bulkheads to the top of each tank. As I alluded to above, the water level may be higher than the top of the drain opening depending on how much flow through you have.
3 - Think about adding a bypass or two. I put one in the plumbing feeding into the frag tank so I could dial back the flow when I wanted to see in without looking through a turbulent surface. I also put one before the main reservoir of the sump so I can cut if off completely when I want to do a water change, thus not affecting the flow or water level in the rest of the system during the drain and refill.
4 - If you have more than 5-6 inches of plumbing coming off of a drain bulkhead (like in the case of valves for a bypass), I recommend using a couple inches of flexible PVC coming out of the bulkhead so you don't end up torquing your glass and cracking it. That happened to me and I had to replace a tank.