[FONT=Geneva]Hello,
We are new to the world of goldfish.

Materials we have:
Rectangular Plastic Tank (Length = 11in., Width= 7 in., Height = 7.5in)
Mineral Block
Multi Color Gravel
Imitation Plant
Food: "Sera Goldy Color" granulated food
Water Conditioner: "Sera Aqutan"

Instructions we were given: We were instructed to feed 3 granules (maximum per fish), partial change of water every 2-3 days, 5-8 drops of Auqutan.

Started with 2 Fantail Goldfish (white + orange/red colors), "Nemo" & "Nemo's Daddy".

Nemo died within 1 week. Bought another "Nemo 2".

Nemo 2 got sick, black spots first one, then over a period of a month more and more balck spots on the torso and fins. It would float on its side, sporadically swim, would be fine for a few days, then continue on as it was on its side...finally Nemo 2 passed after reviving himself 3 times. I have read that the black spots are called black smudge? due to high ammonia levels?

Anyway, we are left with 1 fish ("Nemo's Daddy") and he has been the survivor since we received the goldfish. Over time, we have noticed:

Loss of scales on his sides (more on one side than the other).
Constipation, with stools from normal color to clear and recently a really really long clear stool.
Paling in color on various parts of his body (like a very soft white thin cottony look). He's just not as brightly colored as before.

Recently:
Sluggish and containing himself to the bottom of the tank.
In the past 24 hours has had a loss of appetite.
Fins are closed and not fanned out. (top closed & bottom fins are tucked under)

We were told to add 1 teaspoon of salt to his tank, after Nemo 2 died. We have just done the 2nd water change (with complete water change with water that was at room temperature) and adding the 1 teaspoon of salt.

I have read as much as I can on the internet on what the possibilities are with ailments, however am so confused as to what to do.

We would like to keep the plastic tank as the goldfish are for our 3 year old daughter. Also, we'd like to keep the cost to a minimum until we learn how to take care of goldfish.

Please help. Our daughter is continuously asking "Where's Nemo" and we'd like to get her another fish, however want to make sure we prevent future fatalities.

Whatever guidance that can be offered is most welcome.

THANK YOU in advance.

oops forgot, I think it's a 2.5 gallon tank

Hi hm24210, and welcome to Koko's!

The thing about goldfish is that they are particularly messy fish which produce a lot of bodily wastes (much more than tropical fish). As such, they very quickly pollute a small volume of water, making it highly poisonous and generally very unpleasant for them to live in. That's why we recommend they be kept in tanks of not less than 10 gallons per fish, with strong filtration as well. The other main reason for giving them lots of space is that they grow pretty large - over a foot long is quite common.

I suspect your fish have been suffering from poor water quality because their tank is so small and unfiltered. The symptoms you are describing all sound like ammonia poisoning (yes, you're right about the black smudges - these are signs of healing ammonia burns).

You *could* try and keep your goldfish in the 2.5 gallon tank if getting a larger tank really is not possible for you, but I definitely wouldn't recommend it. I hate to say this, but it probably isn't going to survive very long in there. The only way you might keep it alive is by doing daily water changes of at least 50% to keep the water clean. Even then it's not really going to have enough room to grow and develop, so will probably not last much beyond a year at most, (kept in optimum conditions, goldfish can live over 20 years).

I would suggest either getting your goldfish a larger tank with a filter (minimum 5 gallons but ideally 10 gallons), or to take the goldfish back to the shop and pick a different fish for the 2.5 gallon tank instead. A single betta (Siamese fighting fish) would do very well in it, as they like warm, shallow, still water. Two or three small tetras or guppies or minnows would also be fine. You would need to do weekly water changes of about 30% with these kinds of fish.

This isn't your fault at all, so please don't feel bad about it - your pet shop should have advised you not to try and keep goldfish in that size tank. Goldfish are not actually an ideal beginner's or child's fish, simply due to their need for masses of space and filtration. Small, hardy tropical fish are much easier.

In the meantime, I would recommend a 100% water change in the tank, and adding 5 level teaspoons of salt to the new water. You can use any salt, as long as it does NOT contain anti-caking agents. Dissolve the salt completely first in the new water (not forgetting to dechlorinate and temperature-match this to the old water so you don't shock the fish). This may be enough to perk your fish up within the next day or so, but as I mentioned ,you will need to do daily 50% water changes from now on to keep the water clean, with salt added each time (to keep the level up at 5 tsps per gallon) until the fish is completely well again. After it has recovered you can stop adding the salt.

Hope this helps, but if you have any more questions please do post again.