Styx I would also like to welcome you and throw my 2 cents at you too. Well Toss it anyways. OK where I live in GA and in my GH I can water my Cattleya types every other day, but I have alot of air movement during the day. If I were you I would put your cat outside where it would get morning sun and or evening sun but protected during the mid day. You can leave it outside utill the temps get down to 55 or so. Since you got it from boxstore I am assuming its not a species and would be probably a Pot. Thats what I see alot of here in Ga. Being outside it will dry out faster too. This is a good thing, but it means watering more. If your really worried about over watering go grab some bamboo screwers from the grocery store and use them to stick into the center of the potting media when you think it should be watered. If it comes out damp don't water, if you cant really tell then wait another day, and if its dry then water. I use the bark bought from Lowes and I think it is the same kind as your talking about. Does the bag have purple in it? It works for me, I only use it for my cats and a few others. I mainly use Sphag, but may be changing that on some more. I find that the size of the bark is ok for the bigger cats, but I cut it down with shears for smaller plants. Just cut enough to pot what you need. The only stuff I have bought already small was seedling mix because it is really fine. Don't be freaked out by all the different "rules" for orchids. They are basicly guidlines. NO ONE I know would ever tell you to put a Cat type orchid in Sphag, but I have one in it in a pot and its growing great. Its still small and not mature enough to flower but its groweing and has roots coming out the airholes and wrapping around the pot. I have a Cat in a basket with sphag, and its growing good too. It dries out really fast being in an open basket so thats not as bad as a pot in sphag. I just wanted to share that with you to let you know that nothing with orchids is absolute. Everyone can so things that others can't. Even if those people are neighbors. Your going to kill your share and your going to have your share of successes. The best thing I can say is just pay attention to your plants. I call it bonding . GOOD LUCK!!