Spot treat an area with a shot of H2O2 (which can be bought about any where, usually in brown plastic bottles). I found that it spreads around a 2.5-Gallon tank quickly, though, and causes everything to bubble (which Bob didn't seem to notice; it didn't bother him, and I think extra oxygen wouldn't bother common freshwater fish). Within an hour or so, or as long as overnight , the BBA (short, dark, hairy looking stuff) begins to turn a sort of orangy red, rather pretty actually... and eventually it dies away. The treatment seems to last a long time, too. I also had BBA in some water sprite (in my 10G tank), in the center of the plant, so I poured H2O2 there (maybe a tablespoon full), and it worked fine.
The only ich I have dealt with was in September of 06, I believe, not long after I set up my 10 gallon. I had some cory cat fish and some black neons and I think that was all (I have it in a diary somewhere at home). The BNs developed the ich. I raised the temperature and added a little sea salt (which I use in the kitchen anyhow), then got on line and started reading everything I could. Someone developed a natural cure that I twisted with my own ideas: more sea salt (maybe totally 2-3 tablespoons over the course of the treatment), a tincture of chile powder (local roasted and ground red chile) to scare the ich, maybe a tablespoon or two; no doubt some bits of fresh garlic, also to scare the ich; a few sprigs of fresh mint (scary and gives fish fresh breath); and a few slurps of aloe vera juice to heal any ich scars. The ich disappeared pretty quickly, no fish were harmed at all, all the plants were fine, and I eased the temperture back down from 84 to ~78, but I waited a month to buy and add the glowlight tetras I had planned before the ich, since ich has a life cycle one has to take into account. Raising the temperature might have been enough... but I like to experiment with natural remedies if I'm sure it won't actually do any harm.
At the PetSmart on Eubank I think I have seen a fish or two in with their plants. More fish in with the plants at the PetCo. And a fish or two in with the plants at Clark's on Lomas. In all cases I thought maybe the fish got in there by accident (or via a customer). Lately I notice Clark's plants do have a lot of algae growth, so if I were to buy any from them, I'd probably give the plants a quick dip in H2O2. Not a long dip though: I did that to an anubias nana one time, letting it soak for 10 or 15 minutes in straight (3%) h2o2 to kill the algae, and the plant nearly died... but it has returned, so it wasn't a complete, expensive (~$8) loss, whew! From now on I'll only add h2o2 to water, or for a new plant maybe swish it in h2o2 quickly (15 or 20 seconds maybe).