Hi Wetfish,
you do not need to treat Polypterids against ick because they are almost immune against it.
The most common parasite on polypterids are Macrogyrodactylus polypteri, this plague will kill a bichir without treatment. The medications against ick don't help against this parasite!
Macrogyrodactylus is a survival artist. The most fresh imported bichirs are dying by this parasite! Here in Germany i've helped some keepers and dealers to handle this problem with Flubenazol. Those who thought they could handle it with common medication against ecto-parasites or salt took the award of 100% lethality of all bichirs the kept. In one case a dealer had the affection of every bichir (ropefish, lapradei, endlicheri, polli, delhezi, ornatipinnis, weeksi and ... teugelsi!) ... i gave him the medication (i have enough of this compound at home, it's medicine for pigs - smallest package 500 g) and all bichirs survived. Another deale who had an affection at the same time uses salt - and lost all bichirs ...
All the way, the dealer with the bichirs thar survived said "Thank You" in a very special way - i got a teugelsi as a present!!!
That's the way i got my teugelsi ...
Greetings
Uwe