Hi Dewayne,

I'm no expert by any means but I'll give it a shot. Adding a water supply may depend on what type of soil is in the pond and if it seeps or leaks, also how much evaporation loss is in your area. If you are losing more water to seepage and evaporation than average rainfall then addition water supply may be needed.This may be something to monitor if the pond is already full with it being the summer and all.

That my take, someone probably has more info