White fluffy stuff on Oscars eye and fins

Question
I'm petsitting a 14 year old oscar.  Recently his mate died, and he's been really down and a little sideways.  A couple of days ago, of course as soon as their owners left.. Oscar's roomy, a pleco, died.  I stressed the aquarium when I tried to move it to get the pleco out, and it cracked after I left (am I the worst fishsitter ever??) and thankfully, while most of the water drained out, there was still enough to cover Oscar the oscar.  When I discovered him the next day, he had a white fungusy looking problem on one eye and one fin.  I had noticed the day before that he seemed to have some crusty white spots on the edges of his fins, not severe enough for me to be sure it was a problem.  The pet store recommended Maracyn Plus, which I gave him yesterday afternoon and again today.  I also got him a 10 gallon tank to hold him over until they get home, they just bought a new 110 gallon aquarium, but didn't want to move them before they left, didn't want to stress them out, HA.  He actually seems to have perked up since the pleco died, in spite of all of this.  The white fluffy stuff might look a little better today, hard to tell.. if this is the right treatment, would it be noticibly better by now?  Does it sound like the right treatment?  Will Oscar be okay in the 10 gallon tank for 4 more days?  The pet store has another pleco that needs a home, she's smaller than Oscar's old tank mate but still really big, about 8" long, is it safe to put her in with Oscar, once this white fluffy problem clears up?  Thanks so much for your help, Oscar is quite a character, his parents very attached to him, and so am I!  oh jeez one more question, he loves crickets, is it okay to just let him eat crickets right now?

Answer
Hi April,
 You are not alone... these sorts of things always happen when people go away.  

1. The eye issue will probably clear up and Maracyn is a good choice.  Be careful not to overdose him. It can take a week or more to see improvement.

2. DO NOT put any other fish in the tank with him.  That would be a VERY bad thing to do and a catfish would be about the worst possible choice. The reason is that he will likely attack the new fish and kill it.  It will die and catfish when they die often pollute the water badly, which could kill him rather quickly.  

Will he be okay in a 10 gallon tank?  Possibly. It depends on how large he is.  It would be a good idea to change about 25$ of the water once a day just to help him stay healthy.

Yes you can feed him crickets, but give him only a few.  It is better if he starves a little rather than has excess food, particularly since he is in a very small tank that could easily become polluted.

-- Ron
  rcoleman@cichlidresearch.com
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