Could this be fin rot?

Question

Both my daughters goldfish have black on the ends of all their fins... it seems to have gotten worse in the past little while.

What is it and how do we treat it?

Answer 1

Yes it probably is fin rot.  Goldfish produce a lot of waste and make the water go bad more often.  The water needs to be changed more often.  To treat the fin rot, go to the pet store and ask for medication for fin rot.  I use melafix which takes care of quite a few problems.  The fins will heal with the proper medication, but the water does need to be changed more often.

Answer 2

In fin rot, the fins begin to fray and get ragged, becoming shorter over time. Usually the edges look white, and may even develop a fuzzy growth due to secondary Cotton Wool infection. As the disease advances the area may become red and inflamed, with bloody patches appearing as more of the fin is eaten away. I do not think that fin rot is the case for you. You need to do a water change right away because nitrates cause burns on the fish, if there are enough in the tank. You need to really condition the water for about a day to get chlorine, ammonia, and nitrates out. Ammonia is another cause of what is called 'chemical burn' which is probably what is happening to you goldfish. You should replace 25-50% of the water today and repeat again for the next few days, constantly using water conditioner. Your fish should be feeling better right away.

Answer 3

Fin rot is happens when ammonia burns the ends of the tail. Since goldfish produce alot of waste it makes the water dirtier. You need to regularly change the fishes water and vaccum the gravel. For treating fin rot you can either buy melafix or change 75% of the water and vaccum the gravel. If you change the water and clean everything it should heal on its own. No problem. But with the water that you put back into the tank add extra water conditioner.  

Answer 4

First off I want to say that goldfish are clumsy and don't always watch where they are going. For this reason you need to make sure the tank has no decorations that are sharp or any tight places they can squeeze themselves into.

With that being said when a goldfish has a black spot appear it has been injured in someway. Think of them as the same as a bruise on us. This means that they are healing. Now it is up to you to figure out what injured them in the first place a correct it.

Kudos to you for already doing this. It could be fin rot but I would be more inclined to say ammonia burns. Test the water and make sure that the ammonia is reading zero, if not then do a water change of at least 20% to bring it down.  

Answer 5

Fin rot generally results in translucent fin edges, or a white film on them.  Black edges could be from toxins in the water that are essentially killing the cells (necrosed cells turn black).  More frequent water changes are likely in order, as Goldfish produce MASSIVE amounts of waste, and as this waste decomposes, ammonia (TOXIC) is released, and will quickly leave chemical burns on the fish (especially fins).  Water changes will dilute this.  Also, make sure you're dechlorinating the water before adding it to the tank.

EDIT: Melafix is a preventative that can be used AFTER whatever is damaging the fins is solved.  It will not treat infections, nor will it fight poisoned water.