Half eaten Molly

Question
QUESTION: We have a ten gallon tank with about 20-25 fish ranging from orange Mollies, dalmatian Mollies, neons, and guppies. They are all different sizes/ages. We also have a lot of snails. Ok one of our dalmatian Mollies looked like she had something going on, on her back half and looked like the other fish may have been picking at her. We went away for a week and when we came back her entire back end was eaten off. My b/f wanted to get rid of her before she died but I wouldn't let him so we kept an eye on her and she kind of just stayed at the top but now she is swimming to the bottom and eating and everything and the other fish are not bothering her now. Guess my question is, is this normal did they eat the bad part and then left her go? Will her back end grow back? Is there something we can put in there to help her get better that will be ok for the snails too? Any other info would be appreciated. Thanks

ANSWER: Hi Jess:  20-25 fish for a ten gallon tank is extremely over stocked you should have no more then ten inches of fish in your tank... which would be about 10 live-bearers such as molly's.  The molly'.... they ate her tail off??? That is not normal behavior for community fish.  If they were not fed properly while you were gone then they would take the weakest fish and try to eat it.  At this point she is probably going to be ok... But you are going to have to separate those fish before you end up with water chemistry issues that cause your fish to die.  a 30 gallon tank would fit the bill.  Whomever sold you all of those fish for your ten gallon tank should not be in the business of selling fish.  dave

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QUESTION: Ok yea the molly is missing like at least a 1/4 of her body but she's been bouncing around the tank like there's nothing wrong. They were being fed the same amount they always are that's why I wasn't sure if fish would eat the infected part of another fish if it was sick and leave the healthy part or not. We actually started out with like seven fish and they just kept breeding and breeding and now we have a lot.  Same with the snails. They don't seem to be breeding as much or at all anymore not really sure why because nothing has really changed but it's ok there not breeding anymore. Is there anything I can put in the water to help keep them healthy and heal the molly that won't kill the snails?

Answer
Honestly... I would just let her be... she will mend on her own. Just make sure she is eating... I would feed brine shrimp.  You can contact one of the local pet stores and see if they will give you fish credit for some of the babies.  It is a good way to have the hobbie pay for itself and sometimes pay for an upgrade to a larger tank.  Live-bearers don't need much to breed.. just add water.  If you medicate the tank it will probably do more harm then good.  dave