Guppie tail half eating off help!

[Ccfd48]

Hello newbie here got a 20 gallon fish tank for my son for his one year birthday did like 3 weeks of reading and prep now running into some troubles week one set tank up fill with water week 2 add 5 fishn total angle , two male guppies, pleco, albino catfish cory no prob week 3 add five fish 2 tetra, 2 mollies,2 glofish. Wife thought she seen mollie attack angle fish but not sure come home catfish dead , angle fish dead with brusing now went to put my son to bed and guppie has half eaten tail help....... gold mollie now in timeout tank should I hospital guppie looking for help new to this but trying to do all the right things mess etc

 

[ebondaruk]

it may be fin rot... look it up!GL

 

[boadams87]

http://www.aquariumadvice.com/artic...g-but-I-already-have-fish-What-now/Page2.html