I agree with Matt. I had a CPR 1200gph HOB overflow that worked for years and THEN....I had syphon issues almost everyday. I am working 4-1/2 hrs from home. Imagine some of the phone calls from "wifey". Not very pretty and I even left to go home at 9:30 p.m. at night because she couldn't get it fixed and water was at the limit the sump would hold. I then drove 4-1/2 hrs back to my job and was at work at 6:30 a.m.. I had to put "RED" tape on the things she needed to unplug to keep from flooding. I had my tank drilled at the top and installed a HOBOGATO Calfo and I am worry free! The best thing I have done as far as my tank! Think about it real hard. If I can be of further help let me know.

Steve