Best to buy your mix from a local orchid society or online.

Here is one place I've bought from but there are many others. Its worth the extra cost because it holds up better.

Jane

orchid mixes

They are the best-I get almost all my media from them! Every now and then I go to a more local store, but their bags are clear so I can see what I'm getting.

I mostly use lava rock. I think the same that they offer. But I buy a 30 lb. bag for much less than their small bag. Maritza, if you joined an orchid society people get together and order bulk and save money. One of many benefits to belong to an orchid club! Your bag looks terrible. Get your money back or throw it out. If you can water every day, depending where you are and which orchids you are growing, use lava rock in a clay pot. To water less than daily adjustments are required.

Thank you all for your advice, I will look for a place you tell me to buy the substrate. I have some dendros in lava rock and they are nice but I water them every day. With the phals the lava rock does not work well, I do not know why. Greetings.

In most cases (I'm sure some differ), orchids can be grown in any media you like, just that the media requires different culture. That being said, what you've shown wouldn't be anything I'd like to grow on.