Two possible and maybe related issues in regards to enclosure. Tank cycling can be stressing frogs (have ammonia and nitrites). Also, frogs are overcrowded (15-20G recommended for 2 ACFs); unless you actually have African Dwarf Frogs (ADFs). What size are your frogs snout to vent (SVL) and do their front legs have webbing between toes?
I have clawed frogs, and I'm thinking that as well, but it doesn't explain the the fecal that I saw =T. The female frog SVL is about 1 inch and the male frog about 1-1/2 inches or less. They have webbing on their toes but not their hands.
If they have parasites; above water quality issue might have stressed frogs and with lowered immune system the parasites have an upper hand. Check with local veterinaries for one with amphib experience to conduct fecals on both frogs. If none, try to get in touch with
Dr. Frye and see if he can do them. Reason for fecal is that it could be a protozoan or a worm infestation and they require different medications. Let us know about the species and size, good luck

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I was thinking of going to a local vet but I have no experience in going to one, I'm afraid of being overcharged.