I came home this morning from a trip out of town to find that approximately
1/2 of the water in my 3,000 gallon pond had drained out. Not going to
bother you with all of the particulars of how but it's not a liner leak and
I was able to stop any additional water from draining out. I've been ponding
for more than 6 years and the pond is home to approximately 25 koi and
goldfish and an assortment of plants. The fish vary in size from two feet to
5 inches. I need to get the water level back up but I'm not sure what the
rules are for filling a pond in the winter. (It's currently 29 degrees
outside and projected to warm into the mid 30s, then back below freezing
tonight.)

In the summer I often top off the pond or do occasional water changes but
never much more than 10%.

Here's my question: Does the 10% rule hold in the winter and, if so, how
long before adding the next 10%?

TIA

John