My 2 goldfish friends.

Question
I have had 2 fancy tailed goldfish for about 3 months now. It's an upright tank that holds about 9 to 10 gallons (8x8 square and 12.5 inches tall). All has been well. They are pretty dirt critters so I try to clean about half the tank every week to week and a half. There has been the odd time that the tank just does not come out as clear as it should so I drain the whole dang thing and let it set over night while "gene and Sally" rest in a small fish bowl. This time I did what I usually do when I clean the whole tank but I noticed that Sally seems to be struggling to float mid tank or lower. She appears to be trying to swim to the bottom of the tank but is clearly struggling with this and then floats to the top. Gene seems to be doing fine though. They have been in the new tank water for 2 days now but I'm getting concerned about Sally. Do you think she will eventually adjust or is there something I can add to the water to make it easier for her? I put in the usual Aquarium salt, Aqua plus and Cycle to the water.  Any advice would be much appreciated.

Answer
Hello Catherine,
To begin with, moving around these fish so much tends to stress them out. You want to do partial water changes only - every time you move them out and then stick them in completely new water it shocks their systems. Not to mention by draining out all the water every once in a while your tank is constantly cycling - which is always a stressful time for any fish.
Get a larger tank - 20 gallons would be much better than 10, and 30 gallons would be best - especially since you have two goldfish which you correctly stated are "dirty critters".
Goldfish are large-bodied, and they process their food much faster than other fish, meaning all in all they create a massive amount of ammonia fairly fast. Without a large body of water to dilute this ammonia, they are very susceptible to a premature death.
No matter what kind of fish you have, the bigger the tank the better. It means less cleaning for you, and more breathing room for the fish.
Once you get the larger tank, only do partial water changes each week - about 20 percent for the 20 gallon, and 30 percent for the 30 gallon.