velvet disease?

Yesterday looking close at my fish I thought some of my cherry barbs looked dusty. After dark I shone a flashlight on them and some of them had glittery, gold/bronze colored patches especially on the top of the head. My first thought is velvet disease, but I don't see any other symptoms- none of the fish are flashing, clamped or lethargic, and they were all eager to eat this morning. I had a thought to check on my betta in the smaller tank last night too, because in the past I've often thought he looked a little 'dusty'- I'd assumed before that his scales are just not very shiny/metallic. When I put the flashlight on him, I thought I saw gold specks gleaming under his gills and along his sides. But if Oliver has it, he's had it coming and going for a long time- how is that possible without my fish being dead? Is it because I feed them garlic about once a week? I don't know.

I went and bought some Kordon Ich Attack. I'm starting treatment today, raising the heat (the disease organism is very similar to ich) and am thinking about doing a three-day blackout, at least on the big aquarium. The velvet organism uses light as well as parasitizing the fish, so denying it light hinders its reproduction. It would have the added benefit of killing off some of my algae problem, too.... Advocates of just using blackout and heat (and sometimes salt) to kill velvet say wrap your tank in black plastic for over two weeks! That would do away with all my plants too, though- so I thought a three-day stint would slow down the velvet, without outright killing the plants... Not going to wrap the tank until I'm done raising the temp, though- it's hard enough getting in/out of the corner where the heater themostat knob is.

Going to keep a running record of how this goes as before- and report at the end of it. I don't know how the fish came down with velvet as I haven't had any new introductions (or illness) in quite some time now. Must have been harboring it in the tank...