Feather Fin Catfish

Aquarium salt in a discus tank? I don't think you want to do that with fish that prefer low TDS. But about the temp - I think that's too warm for them:
http://www.planetcatfish.com/catelog/species.php?species_id=121

I have a Synodontis eupterus who has been fine when I've treated for ich in his tank by keeping the temp at 84 for 7-10 days - but I used tons of extra aeration and it did seem to "agitate" him somewhat, he dashed out during odd hours (usually late in the evening is the only time I ever see him)
 
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