Hi George, are these bilge pumps you used. I have been using fountain pumps made for continious use, mine are 110volts but they also have 12 volt fountain pumps. Check out Nextag they have a few different models. I must tell you though I dont run my pumps at night. But they have lasted almost a year now and they are some cheap china pumps.Good luck Mark
Hello Mark. Yep, they were bilge pumps. Will look at the fountain pumps. Thanks.