I have 2 different goldfish that have a dark colored like grayish color on the fins. What could this be?

Question

They both seem to swim fine, but I had an algea eater, that the fins looked funny like they had destroyed but I bought it like that and didn't think anything of it.. But like I said earlier its just a grayish blackish color that were at little parts of the fins. It's not ick either I checked that... My guess would be a parasite or a fungus. Can anyone help me???

Answer 1

Can you give a better description of what's happening? Here are some thoughts, but more info would be needed for anything approaching a firm diagnosis of the problem.

It may not be an illness at all, just a color development; goldfish may go through several color changes in their lives. Dark-edged fins are a common development. Look more closely at the colored areas. If they seem like simply different-colored scales, that may be exactly what they are. On the other hand, if the colored areas seem raised above the scales, like something growing on the fish's body, then you have a problem.

Ick is a parasitic infestation and doesn't even remotely fit this description, although people often seize on it as an explanation for ANY illness in fish.

A bacterial infection would show a slightly raised whitish edge, along with a line of fin degradation.

A fungal infection would show either a fuzzy whitish-greyish growth, or simply a raggedy fin edge with deep cuts and no visible growths on it.

Another possibility: fish will "lose color" from being generally unhealthy. This doesn't mean they have a specific illness; it means they're being kept in an inadequate environment and are stressed. This especially happens to goldfish being kept in bowls (which are NOT proper environments for ANY common pet fish, with the single exception of "fighter fish" or bettas). Are your goldfish active, with fins spread out nicely, not clamped into the body? Are they being housed correctly - minimum 2 gallons of water per inch of body length, with a filter or at least an aerator? Are you varying their diet (occasionally feeding brine shrimp or spirulina instead of flakes), while being careful not to overfeed (quick rule of thumb: a fish's stomach is approximately the size of its eyeball)? Are you regularly changing part of the water to keep nitrate wastes from building up?

As for buying a fish with damaged fins, I wouldn't do that unless you're knowledgeable enough to treat the problem AND have a quarantine tank (or are prepared to take the consequences). Fish often peck at each other in overcrowded dealers' tanks or delivery boxes; it may be injury, not illness. However, an injury can become infected after the fact. Best to leave that fish in the dealer's tank! Fins looking "destroyed" sounds like fungal rot, if I had to guess from just that word. If that algae eater is still alive, it may need medication. Plecostomus seem particularly prone to this problem.

Good luck to you (and your fish)!

Answer 2

your goldfish may be going through a normal color change or they could be damaged by the algae eater

do not keep algae eaters or plecos with goldfish, they will harm or kill the goldfish besides the fact that goldfish do the same job that the algae eaters/plecos do

Answer 3

If it looks fuzzy, it's probably fungal fin rot, which is easily treated with malachite green + formalin (Quick Cure, Rid Ich) or copper (Coppersafe, Cupramine, Aquarisol, Organicure).  If using malachite green, turn off the lights during treatment, as it degrades with exposure to light.

If it's just like the fins are deteriorating, it's probably bacterial fin rot, which you can easily treat with Maracyn + Maracyn 2, Maracyn TC, Triple Sulfa, Trisulfa, Furan 2, Kanaplex, Kanacyn, or similar medications.  When using Maracyn TC or Maracyn 2, keep the lights out for the same reason as the above malachite green.

When treating, remove all carbon from the filter, as it removes medications.

Bacterial fin rot: http://208.112.95.51/CypriniiformPIX/Gol...

Fungal fin rot: http://forum.discusnews.com/albums/album...