GF Piping Systems 192304006 PVC Y Check Valve - 1/2" Spigot, EPDM Seat & Seal, Wye Style for Water & Chemical Flow Control - Ideal for Plumbing, Irrigation & Industrial Applications

I use this for my 36 gallon reef tank (fish and live coral). I have several thousand worth in live coral and can't afford too many mistakes when it comes to plumbing, filtration and water circulation. At the same time I can't afford a power outage that allows the exhaust water to backfill and flood my home. I researched several types of Y style check valves and after talking with Dr. Mac at Pacific East Aquatics in Marydel Springs, MD I went the extra mile for this check valve over a few cheaper styles that were sure to fail over time.After installing it and using it for a little over 2 years now it's never failed once and eventually you WILL have a power outage. Also very easy to clean and access the interior parts which you can't do with other models or style of check valves.Having previously owned a 90 gallon reef tank it wasn't uncommon to come home to find 20-30 gallons of saltwater on the floor due to whatever reason for a power outage. That's both time and money as well as clean up costs down the drain. Luckily with a larger tank you have a lot more forgiveness in temperature swings and chemical changes. In smaller tanks thats not even an option. Othe roptions including carefully placed pinholes in the uptake tube or U tube sometimes worked but were never guaranteed if something happened to plug it up including algae growth or a snail, etc.For me this was an absolute answer to a years old problem and it works 100% of the time. Quality of the parts is nothign to sneeze at either. Very durable non UV effected plastics and seals.