I am a big fan of preparing for the worst when it comes to keeping a reef tank and I constantly think about ways to prevent potential disasters before they happen. On several occasions in the past, my skimmer overflowed without warning and nearly dumped skimmate into my sump. I was lucky because I caught it early but it made me wonder how I could keep this from occurring in the future.


Some folks use waste collection containers connected to the skimmer cup to catch overflows but certain containers, when full, will not prevent waste from continuing to overflow onto the floor. However, other devices will shut a skimmer off when the container is full, although these automatic shut off containers can be pricey.

The DIY Route

I was on the hunt for a cheaper solution so I began to noodle around with some DIY ideas. The plan was to use my controller to shut the skimmer off when the switch was triggered.


The lid on my skimmer has 4 large holes, which made me think it was possible to install a float switch vertically through one of the holes.


Ok, the wheels were turning! I ended up buying a standard float switch, a 5/16″ nylon screw (2-1/4″ long) and 3 nylon nuts. The float switch cost $10 and the screw and nuts cost $2. A $12 breakout board was also needed to hook the float switch up to my controller.


The top part of the float switch was threaded so my plan was to utilize those threads to attach it to the nylon screw with one of the nuts. Now, the challenge was to find a hollow nylon screw to thread the wires of the float switch through it and out the top of the skimmer. Of course I could not find one anywhere but the guy at my local hardware store was able to drill a hole through the screw with a 1/8″ drill bit. Let me tell you, it was not easy! Using a drill press would have been much less painful.


Skimmer Float Switch


Below are two videos explaining how to connect the float switch to either a Neptune Systems APEX controller or a GHL Profilux 4 Controller.




Whether it is this gizmo or something else, it does pay to be proactive about preventing potential disasters. As the saying goes, an ounce of prevention is worth a pound of cure!


Shop Profilux 4 Controllers Now



If you are looking for additional insights and information, please explore my many other reef tank and SPS related articles as well as my book, A ReefBum’s Guide To Keeping an SPS Reef Tank: A Blueprint For Success. Additionally, you can see all of my reef tank videos online now as well as my Live HD Webcam. And if you are interested in purchasing affordable SPS frags that are pest-free and homegrown, you can visit my SPS Frag store.


Happy reef keeping!