The boat will need four scoops for two ballast tanks or some sort of interconnect that balances the tanks.
Some people use Andersen Super Mini Special dinghy bailers These look heavy and expensive although durable. They may be a bit small.
Here is a good looking carbon design. This is the only picture I found and it does not show any of the internal mechanism
Jan Gougeon's boat Strings as well as his earlier designs used this type of system. Again, I am lacking details. Here is a picture of a control center for Strings' ballast system.
Perhaps YOU have some experience you could share with me.
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