I have 2 large dogs that are outside during the day. They have a covered area with their food and a house. They also have a dog run with a sunshade and water bowls. I was thinking of putting in a sandbox and a mister to keep the sand cool. Someone suggested I use cedar mulch instead...that it will keep cooler when wet and repel bugs.
Which would be the best?

Have never thought of doing something like this before. But the first thing I thought of was, with the sand you will be making mud for your dogs to lay in, and they will be tracking in the sand on their fur when they come in. Also unless they are cat killers you are making a very nice litter box for the local kitties. So if I were going to try something like that I would go with the cedar mulch.

We have a hard plastic kiddie pool for our dog, the smallish kind you can get at Walmart for less than $10. He loves to just lay in the water. The hard part is I have to hide the mosquito dunk under a rock because he thinks it's a dog biscuit and eats it. (then promptly throws up)

I set up a mister spray system along the dog house and dog run. I would not recommend sand since it attracts fleas.

I have a child's wading pool for my dogs and one loves it, the other hasn't been here for a hot summer yet to discover the joy of a quick dunk to cool off. She'll learn by example.

I haven't tried a mosquito dunk because I'm sure they'd eat it or play with it, so I change the water every two or three days (tops). It only needs a couple of inches to do the trick and placing it so the water is in the afternoon shade makes it a nice spot of relief in the hottest part of the day. I move it around the yard and position it near a plant each time so I can dump the contents on something I want to have a deep watering. With about five specific plants to water and this rotation program they each get a deep watering every couple of weeks.

Northwesterner