I wouldn't worry about the spots on the leaf unless they seem to be visibly getting bigger. Most Oncidiinae get brown spots on their leaves, espicially at the tips, when they're given enough light to bloom strongly. If, on the other hand, the spots are mushy, wet looking, and getting bigger, that's fungus or bacteria. You should wipe a pair of scissors down with alcohol and cut the leaf about an inch past the bad part, toward the plant. Most people cut an outward "V" shape to make the cut look more natural. But if the spots in your picture are the only ones on the plant, that's perfectly normal, and not worth fussing with. (Orchids are grown for their flowers, not their foliage, so even though many people want and expect an orchid plant whose leaves look pristine, it's usually not possible. Matter of fact, many of the silk plant manufacturers have started adding "defects" to their orchid foliage to make their product look even more lifelike...)
That's completely up to you. Attaching plants to a slab of bark or cork makes them look more like they would growing in the wild, and I like that effect. Just remember that you'll probably have to water the plant more frequently than you would if you planted it in a pot.When I repot, do you recommend attaching it to bark, or in a pot?
I've never used that brand but the numbers look alright. We usually recommend balanced (10-10-10 or 20-20-20, something like that) fertilizers but I'm sure what you bought will be just fine. Remember, too, that you should dilute all the fertilizer mixes from 1/4 to 1/3 strength, not just the bloom booster. About the Urea, it's only useful in fertilizers applied to plants growing in soil, (lawn, shrubs, etc.) since Urea needs the microbes in soil to break the nitrogen out of it. So, yes, what you bought will work great.Another thing I was wondering was that I have Better-Go fertilizer that I just got today too. The regular is 20-14-13, and the bloom booster is 11-35-15. No urea is in them which as I have been surfing the internet is a good thing. Is this adequet?
Use the bloom booster on a plant when you first see it start to spike, and apply it (dilluted again) at the same frequency as the regular fertilizer (usually about once a week.)when do I start using the bloom booster? I know to use it half strength, but how often? Do they all need it at different times?
Adding pebbles may help the water evaporate faster and increase the humidity, but it's not crucial. As long as the pot isn't sitting in a trayful of water... As far as misting is concerned, some people love to (because it makes them feel like they're doing something good for their orchids) and other people never pick up a spray bottle. If you're growing in a dry environment, a morning misting will help keep the plant's leaves from getting too dried out. It's not necessary to drench the leaves when you mist, just a light spray is fine. And be sure that the leaves are completely dried off by nightfall, otherwise fungus could result. So if it would make you feel better to mist them, then go ahead!!Do I still need to add pebbles? Does misting the leaves help? How often do you mist the leaves?