I currently have a water circulation pump that runs continuously. My system has a dedicated return line but the original plumber has some fixtures fed from the hot line and some from the return line. Not sure if that is normal but it is how it was originally plumbed. The issue I am having is with a 50 gallon tank I am completely out of hot water within about 13 minutes of starting the shower(Luke warm at best by this point) on top of this issue, if I take a very quick five minute shower, within a few minutes of turning the water off, the next person can turn another shower on and the water is significantly lower in temperature. Is this a by product of the continuously running pump. If so what options do I have to address this?