Last year you helped us out with a bunch of questions for our new pond. With the sudden increase of the weather the surface water temp is over 50 degrees during the day. Should I feed my koi yet or wait? They seem to be pick at the algae on the rocks but I didn't want to hurt them by feeding them to soon and have a dramatic cold spell?
One addition question is Blue stone chip safe to put around a pond? I wanted to make sure the rain run off from the blue stone chip to the pond will not hurt anything? I have bigger midnight blue boulders in the pond and it seems not to affect the pond.
Surface temps can be very misleading unless your pumps are on and your water is thoroughly mixed. DO NOT FEED until your deep water temps are reliably above 55 degrees throughout the night.
I am assuming that blue stone is dyed marble or limestone chip. Ask the supplier or manufacturer if the dye is fish-safe.