When it comes to topping off your aquarium, there are a variety of ways to automate the process. For instance, it's fairly common to utilize an auto top off system, such as the Tunze Osmolator. You could also hook your RO system up directly to your sump. It's important to look at your aquarium set-up and consider how much time and money you've invested when evaluating what level of redundancy you require. If you're anything like me, you want your tank up for 10 years not 3, and will want a higher level of redundancy. With that said, there are two types of float valves you can choose from: adjustable and non-adjustable. With the adjustable float valves, it is nice that you can adjust them, but the wing nut unfortunately can be a point of failure - if it loosens over time the float will be useless and flood the tank. The non-adjustable valves have a permanent off-position and are much safer. Another easy form of redundancy for your top off is a leak detector which is a battery operated valve that turns off the probe if water is detected. The probe is about as simple as it gets; just two metal pads. If any moisture crosses them, it creates an electrical connection that triggers a valve and an alarm in the leak detector. One interesting thing you can do with a leak detector is to add some electrical clips to the end of a float switch and attach at the end of the leak detectors probe. Install it above the float valve; if the valve ever fails, the switch will rise causing an electrical connection which triggers the leak detectors valve and audible alarm. If you have a Neptune Apex controller, you can utilize the "ALD" or Advanced Leak Detection module. There are two options to choose from; the "solid-surface" leak detector probe and "low-profile" leak detector probe. You could also use a digital timer with a powered solenoid to further increase the redundancy by restricting the amount of time the solenoid is powered and open. For instance, if my tank evaporated around a gallon a day I could set the timer to only power and open the solenoid for 25 minutes once a day which should be sufficient on most seventy five gallon per day systems. The last bit of advice if you use a leak detector or solenoid, be sure to put it in line after the RO system or after the DI stage. If you haven't already hit that subscribe button because we release new videos every Tuesday and Friday. See ya next week with another episode of BRStv. Connect with us on Facebook: http://www.facebook.com/BulkReefSupply Check out our pics on Instagram: http://instagram.com/bulkreefsupply *Legal Stuff* The purpose and content of this video is to provide general information regarding the products and their applications as presented in the video. Aquatic Sales Solutions, Inc. and its officers, directors, employees and agents disclaim all express or implied warranties, in any way, related to the products and their application as presented in this video, make no representation or warranty regarding the products and the application as presented in this video and shall not be liable for any direct or indirect losses or damages of any type, including but not limited to punitive damages, or from personal injury or death resulting from or in any manner related to the video, and the products in and contents of the video. The viewer expressly agrees that aquatic sales solutions, inc. And its officers, directors, employees and agents shall not be liable for any damages or losses related to the products in and content of the video and hereby agrees to hold the foregoing harmless from any such losses or damages.