Going back to my days of etching circuit boards....

Aquariums make good containers. Can be free or really cheap if you find
the right yard sale or craigslist posting.

Heat can help. Aquarium heaters are handy for that.

One method of stirring is to run an aquarium bubbler-stone under the
workpiece. Aquarium pumps/filters can also be used. You may see a theme
developing here....

Don't try to use (or let someone else use) an aquarium used for plating
or etching for fish...

You may want to experiment with different electrolytes. Washing soda
(sodium carbonate) or baking soda (sodium bicarbonate) instead of salt,
for instance.

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Cats, coffee, chocolate...vices to live by
Please don't feed the trolls. Killfile and ignore them so they will go away.