fish in outdoor rain barrell

Question
Happy with my new effort at water conservation I have added a 50 gallon rain barrell to my Florida yard.  I would like advice about fish that could be added to eat the algae and mosquito larvae.  I got 2 Otocinclus and 15 Platys.  But in first 2 days 10 platys have died.   Since the pet store called them "feeder fish" I thought they may have just starved unfed.  I tried feeding the second batch of 15 but am losing some of them too. Advice?

Answer
Hi Minu,
 There are fish called "mosquitofish" that you could put in there.  Here (in California) you can get them free from the Mosquito Vector Control board.  I imagine there might be something similar in Florida.  

-- Ron
  rcoleman@cichlidresearch.com
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