Hi Ken,
Sounds like you got "suckered" into the hobby the same way I got involved,
only my kid had the first fish from a science class project. Do yourself a
favor, and don't even bother with the little tanks. These fish grow
incredibly fast, and the ten gallon rule is a misnomer. In reality, your
fishes total body mass is what matters. One ten inch fish weighs more than
ten one inch fish . . . by a lot!
My three goldfish came in stages. "Sharky" is 16 months with us, and is
already at least 12" long, without including his long tail. "Face", our
female was bought as a companion, and she has been with us for just over one
year. She is already about 7 or 8" long. And "Gemini", our other male, came
along just under a year ago. He is already at the 5-6" mark, with no sign of
being done growing.
My original thought was that a 20gallon tank would hold these three fish for
a lifetime. So I started out that way. Money well spent, or so I thought,
till they outgrew it in three months. Now it holds a variety of small
tropical fish. The next upgrade was to a 75 gallon tank. It has held them
very well till now, although I did have to add a second large filter system
to keep it clean. And I do water changes almost every other day.
The idea that you can get away with only adding water is simply wrong. You
must drain off the 25% to purge nitrates, and then top off with fresh
dechlorinated water. If not, the nitrates will certainly build up very fast,
and you are going to have trouble. I am currently having my first health
issues because of water conditions, and I have been almost religious about
tank care and water changes. There is simply no solution to polution other
than dilution. I hear it from the most knowledgable people all the time.
In this short amount of time, I have arrived at the point where I have to
make a choice . . . either build a pond, or find a nice pond for my fish to
go to. I don't think they will be happy for much longer in the tank I have,
and I don't have space to add an even larger tank. It wouldn't matter
anyway, as these fish grow to match the size of the environment they live
in. Our local reservior has carp that are at least 3' long, and lord only
knows what they weigh. They all started out as goldfish that people dumped
out there.
It seems that most pets are sold with adequate information about thier needs
and eventual size. Why they don't do that for goldfish is beyond me. These
are among the most demanding of fish to keep properly, and none of the
stores inform people about thier eventual needs. They are considered to be
"disposable" fish for some reason. Only a person who has kept them for any
length of time can realize how smart they are, and how much personality they
have. They are a noble fish, worthy of the best we can offer them. So if you
plan to keep them for any length of time, go right for the largest tank you
can handle, don't overstock it, and always do proper water changes.
Hope this helps some. Best of luck!


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These ideas are offered in a spirit of respect, compasion and the intent to
foster enlightenment. Please feel free to respond with similar intent and
respect. Growth comes from discusion divorced from negativity and/or
contempt.