<pinches TPIRman's cheeks> What a schweethat.
Yah, I would try to find some of that Parasite Guard. Even if you have to order some sort of online med - it can save some of your future fish at least. Say only 8 of your fish have it right now (maybe it's too late to help them), well, if you order the meds now, it might be there in time to help out the other fish that may develope it soon.
Some people will say that it's useless to treat the water when dealing with internal parasites because they're, well, internal. I think it's worth a shot - heck the fish live in and absorb the water. Plus, for anal worms that hang out, swishing around in medicated water must have some sort of negative affect on them.
You may want to check the Discus food to see what is in it. I'm not exactly sure which ingredients in Pepso food are the *ones* that kill the parasites, but if you could get a list of them (one of Jungle's sites must list them), you could compare it to the discus food?
Also, I might as well stick this here. A lot of people have asked about what Pepso food is like and how big it is, etc. I'll include a picture of how small it is. Tetras will eat it, gouramis, rainbowfish, rasboras, etc. It's virtually useless for larger fish and things like otos. For them, soak zucchini or algae wafers in the garlic.
Good luck and let us know how things go!
***EDIT****
Oh, this is a post from Avalon at Myfishtank. It may be of some help to you (again, not sure about availability).
It's very common to have worms that hang from the fish's anus. This is one sign that you are dealing with a serious case. Unlike the post about internal parasites, which is meant as a general and safe introduction to begin, this is one case where you will have to deviate from the "simple" treatments I previously mentioned.
Unfortunately, metro will not help you much here. I will refer a few medications for you to use, but you must keep in mind that with the exception of two, I have no experience with them. I've only heard that they will work and that I do not know the dosages and/or treatment regimine. Use at your own risk. Better yet, call a vet.
Piperazine: also known as pipzine, this med is found in most dog/cat de-worming medications. This med was initially recommended by the owner of a LFS I trust. He uses it and recommends it to discus owners to cure IP's. If found in the liquid form over-the-counter, you can soak you food in it and feed it to your fish. I've use it a few times, but not enough to tell if it worked because my infected fish didn't eat it. My healthy convicts readily ate food treated with it without any negative effects.
Praziquantal: also commonly known as "prazi." This appears to be very popular with discus owners. I've seen information about this med @ www.simplydiscus.com
Panacur(?): from what I've gathered, this is a heavy duty med that should only be administered through food only and never the water column. Rumor has it that it's very effective for stomach worms. Use at your own risk.
Levamisole: This is a very safe and very effective medicine for internal parasites, but I'm unsure of it's effectiveness against worms. Levamisol ranks up there with metro in overall effectiveness, but it's very, very hard to find without a prescription from a vet.
I'll see what else I can find.
Here's another awesome link. I believe they list some sources,too? They talk about garlic and why it may help. The only I'll change offhand is that Pepso food and Jungle's meds are *not* worthless. I've used them exclusively besides garlic to treat infections and they've worked. Though, as I said, he was dealing with large cichlids and the food is too small for them.
http://myfishtank.net/forum/showthread.php?s=&threadid=13065
Sorry the links aren't from here. I'm more familiar with that site.