Tail regeneration?

Question
Hi Karen-
First, thank you for this service, I've just found it and it seems to be a great way to get info.
My question is, do tropical fish regenerate their tails after damage has occurred, and if so, how long does it take?  
Our family has just set up a 10 gallon tank with 2 guppies, 2 platys, 2 silver tetras and 2 neons.  We had the platys and 1 tetra for a week before adding the others.  A day after adding the latter fish, all but the platys had some tail damage (I didn't want to say, but we had put in a flathead minnow my son had caught for a couple of days, and figure he was the culprit - he was removed immediately after the tail damage was discovered - I know, putting him in was a dumb thing to do...)

Thanks!
neal

Answer
Hi Neal,
Most of the time fish can recover from fin damage.It is going to vary as to how long and how bad the damage is. You may start to notice some growth in a week. Just be sure to really keep the water clean. If you don't then sometimes they can get an infection. I would do a partial water change of about 1/3 at least twice a week especially since  you have just set up your tank and it is still in the cycling process. If you don't the ammonia might get too high and cause more fin damage. Ammonia will usually rise during the first few weeks of cycling and you really don't want it to get too high or your fish will suffer. Also, with the fin damage that has already happened, you don't want it to become worse from high ammonia. Just be careful and be sure to do the water changes regularly and things should be ok.
Best of luck with your new aquarium.
Hope this has helped,
Karen