I keep getting the prompt to load java runtime even though I have just downloaded it

Downloading and installing are not the same thing. You should be downloading: Apple Java 2015-001 for Lion thru Yosemite. After downloading the software double-click on the disk image's icon showing on your Desktop. A window should open with an installer. Double-click on the installer to install the software.

Most likely, you have a web plugin that depends on the Java runtime distributed by Apple, such as the Facebook video calling plugin or the "NexDef" plugin for watching baseball streams. If you no longer need the plugin, remove it, including its automatic update mechanism (if any) according to the developer's instructions. Otherwise, install the Apple Java.

To avoid confusion, note that Apple's Java runtime is not the same as Oracle's, and the two don't overlap in function.