platy eye infection?

Question
QUESTION: I have a 5 gallon tank with a betta, pleco and three half-platy, half-swordtail fish (i don't really know what to call them), and while I was on vacation, my sister was looking after them (they used to be hers). I got home today and one of the platies was sitting on the bottom, and has a milky white bubble over one eye, and fluffy white patches on his skin. Can you tell me what's wrong with him and how to fix it?

ANSWER: sounds like pop-eye and a fungal issue. I would medicate him with an antibiotic or general cure... use tetracycline or erythromycin ... dave

---------- FOLLOW-UP ----------

QUESTION: I got them some tetracycline, and gave them the first 2 doses, and the platy is looking better! The box said to take out the filters so they wouldn't filter out the medicine, and now my tank is a really dark orangey color, is that due to the filter/medicine?

Answer
It is good news that you are making progress.  The orange color is from the medication.   You will want to keep your eye on the water chemistry because without the filter media the tank may cycle which could put the fish in danger.  Follow the directions on the package for the antibiotic regarding water changes... dave