Hi,
I live in Maine and have an indoor. We used stone dust(fine) and I put a product called Mag down once a year for dust control no watering needed - as a matter of fact the company recommends that you do not water it as the MAG attracts moisture from the air and holds it- the stuff works GREAT. I swear by it.
It comes in pellets and flakes we use the flakes. I use 10/12 bags for a 72x120 over a two week period. First we drag it then spread 4 bags then let it set for a couple of days then use it a few times to stir it up a bit then apply more and repeat the process. I just did mine and there is hardly any dust. My previous arena was sand and I used the same product and had the same great results.You don't need to be concerned with freezing with an indoor around here even when it's sub zero degrees - but if you are concerned about it the MAG will take of both dust and freezing.We use a hand pushed lawn seed spreader to apply it.Took me about 20 minutes each time to apply.
We get ours at a local Agway Feed store.You can get it just about any where.Here's a link for it.
http://www.meltsnow.com/msds-mag-care-feeding-dust.htmAs far as footing goes - there are so many combinations - stone dust -sand and stone dust mix - sand rubber and so on. Originally we were going to go with sand again and add the Perma Flex or similar crumb rubber product but the stone dust we found was so awesome that we have just stayed with that.We compacted it really tight so it was pretty firm when we first put down - when we drag it- sometimes we go with tines down on the drag to soften it up a bit then if it gets to too soft we drag with the chain side and firms back up-pretty good stuff!If you go with stone dust make sure it clean sifted as there are a few varieties of it some are very stoney - same with sand- you want to go sand that has angular granules not round and make sure its sifted for stones/rocks...Good luck...You want but our place (LOL!)we're moving to Ocala in 2 1/2 years
There is picture of our barn/arena on my photobucket link