Golden Sunray Dend. with black spots

[hevnbown]

My Sunray has black spots on it. I'm assuming it's fungus related. It's very healthy otherwise...it has grown 2 new stems within the last 5 months which is the time I have owned it. So, I purchased some Captan Fungicide but can't seem to figure out how much I need to put in a 24 Oz spray bottle which I had planned to spray all my orchids (for the first time) down with. Can anyone help me on this? Thanks

[Bud]

go online for Captan ratio mix with water. Do you have the powder?
how do you know its really a fungus infestation? sometimes if you leave droplets on the leaves while watering the sun will daken it into spots(sun spots)
fungus infestation will spraed. if its not spreading its not fungi and you need not bring out the big guns on this...captan can be daunting; I will use it only if its a hair raising fungi infestation.

[hevnbown]

I bought the plant back in Feb of this year. It had 2 or 3 very small black spots on it but I didn't pay much attention to them. Just counted the spots...it's up to 8 now. It's definitely spreading. And yes, I have the powder. Where on-line do I go for the mixture for orchids? Is there something better and not as strong that I can use?