my daughters goldfish has developed what looks like black inky looking discolouration to its body and the edge of its fins. It seems helthy enough, i.e movement and appitite. Any suggestions would be greatly appriatiated..

Try to answer as much of the above questions as possible, that'll help us figure out what's going on.

What's most likely happening is that the black-discoloration you're seeing are scabs from acute waste exposure (ammonia). You'll need to do very large water changes either once or twice a week to help alleviate this problem.

Check out the links at the bottom of my post for more information.

We recently purchased goldfish, my daughters fish was bright white and orange, within the past week it has dappled out in black spots, I know that some goldfish do this on their scales but it appears to be forming arround his face, have you found out any info on your fish yet?

Melanie, in your case the fish seems to be suffering from ammonia burns which is caused by high ammonia levels. I think it's best if you start a new thread in diagnosis section and also don't forget to answer the questions in the white box above

thank you nenn i'll get on it right away. Any idea how long this process takes? I think the fish had a white fungus which i treated with tonic salts, and it seemed to go so maybe this is the healing process you mentioned. I change the water on average once every two weeks. I think it is about 8-10 gal tank, no filter, and only one fish remains. She feeds them twice a day with aquarian flake food , but at times other fingers but more than enough food in, which i have stopped by moveing the tank above reachable level. I have never tested the water for the ammonia or nitrate levels. Once again thank you

Hi there fish help

Unfortunately without a filter, this will be an ongoing problem - unless you change about 70% of the water daily. If you were to get a filter (ie. a hang on back type that houses both sponge and ceramic) then it will cycle which means good nitrifying bacteria will grow on the filter media. This bacteria is fed by ammonia and once the filter is cycled, it will convert ammonia to nitrites to nitrates and nitrates are much less harmful than ammonia and nitrites.

Cycling a filter can take up to about 6-8 weeks and during this time, the ammonia and nitrites will climb to dangerous levels (which are reduced by daily waterchanges) and when you see nitrates appear, it will mean the cycle is kicking along smoothly

The problem without a filter is every hour of every day, fish excrete ammonia both via their waste and gills (which is kinda like pee) and the level of ammonia has nowhere to go but up and this is when you see the black smudges on the body. It's ammonia burn that's healing but unless the ammonia problem is fixed, the blackness will worsen and unfortunately your fish may die. They can withstand it for a little while but it stresses them badly lowering their immunity and once this happens, bacteria and illness can set in.

So if you can, try to grab a good filter ie. one that filters about 100 gallons per hour and in the meantime, I would up the waterchanges to daily until the skin heals. This will help your fish enormously

JenW is right about the importance of a filter. It's the goldfish lover's best friend!

It can take up to two months to properly establish nitrifying bacteria in a goldfish tank, but once you do, you've got smooth sailing (as long as you keep decent maintanance).

So in summary:
1. Do large daily water changes
2. Obtain a filter of at least 100GPH
3. Do not attempt to add more fish / tank companions to the aquarium
4. Lessen feeding to once a day or every other day to reduce ammonia output
5. GET YOUR WATER TESTED. Purchasing a MASTER KIT will be one of the best investments you'll ever make when you take up the fishkeeping hobby. You need to know the numbers to accurately determine the health of your fish's home.

Good luck and keep us updated!

Fish is looking well happy now, been changing the water 2/3 times week, a little scale damage but the blackness has all but gone. He/she is swimming around the tank with renewed vigour. Thank you again for your help.

Congrats!

It's always good to hear goldfishy happy endings.

Yes it is. Good work everyone

Could you please explain why i should not add to the solitary goldfish? Is it tank size or an infection issue? As there used to be 2 fish in the tank..thanking you

It was a combination of both. You estimated your volume to be 8-10gallons, correct? For goldfish, they need at least 10-gallons of water volume per fish, so adding more would only stress out your current fish and may bring on more diseases lurking around.

the technical answer to your question lies with what JenW has to say. Fish excrete ammonia (lots there of), as you have a relatively small tank and no filtration the level of ammonia builds up in the small amount of water very quickly, (hence her suggestion to change the water everyday) if you were to add a second fish there will be twice as much ammonia being released into your tank water, hence the ammonia level will builds up twice as fast. You say you're changing the water 2-3 times a week and that your fish is getting better, if you add a second fish, you really will have to consider changing the water every day to stop your fish from becoming sick again... that's why people suggest you don't add another fish, you can, but it will be making more work for you, or, more hertbreak for your kid when the fish keep keeling over.

I always think that it's better for children to keep one fish happy and healthy, so they can really bond with the pet, rather than having to deal with the grief of losing fish on such a regular basis, just for the sake of aesthetics of having two fish, they're social animals, but they REALLY don't mind being alone in a tank.. It can also be good education for the child to understand about proper care of pets and for them to understand that fish are living animals, not just pretty commodities.