guppies dying, fin rot?

#1
my teacher has a fish tank with guppies and a pleco. she just got the pleco and all her fish are dying. when they die their fins are partly, i dont know, just gone. i think it is fin rot from the new pleco, becuase the pleco has fin yucky stuff on its fins. is their anything i can do? any treatmentor medicene? or just let the guppies die, becuase she said the same thing kinda happend last time a while after the guppies had babies. its been about 5-8 months since they had the babies. i dont know, just if any one has any help, my teacher will appreciate it. thankyou.
 

Lotus

Ultimate Fish
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Aug 26, 2003
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#2
I don't know what size tank she has, but it may be too small for a pleco. Plecos add a lot to the bioload, and can affect water quality. You should ask her how often she is doing water changes, as poor water quality can lead to fin rot.

Is what she should do is keep up on her water changes and get some fin rot medicines. There are several available, and I have found most of them effective. Two I like are Jungle Fungus Clear tabs and AP+ Fungus Clear.