Water change frequency with sparsely filled tanks

Okay, so we're moving to a new house, and we've decided to give our 4
goldfish lots of space. We're buying 2 50G tanks. In one tank, we'll
have the two commons, and in the other we'll keep the two veiltails.

Right now, the veiltails get a lot of water changes. Their 15G tank is
theoretically big enough for them (by the inch of fish per G
measurement), but they dirty the water pretty fast, even with a 30G
filter. As we're doing right now, we'll probably put about 15G extra
filtration on each tank (so 65G for a 50G tank).

However, when I do water changes with a tank that big, should I be
doing the same weekly 25% changes with a 45% change every month, or
should I tone that down because the tanks have so few fish? The
veiltails are dirty fish, but I don't think that even they could dirty
that much water in such a short time.

I was thinking of pulling the water change schedule back to 10% per
week, 33% every month, and a big 50% change once every 2 or 3
months. Does that sound okay, or should I just keep on with the
schedule I have now?

JS

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Jan Sacharuk Member in Good Standing of The Discordian Solidarity
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"There is no spoon."

change water as often as needed to keep nitrates around 20 ppm. Ingrid

Jan Sacharuk wrote:
Okay, so we're moving to a new house, and we've decided to give our 4
goldfish lots of space.


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