I have an outdoor pond and want to take the goldfish out while I clean it. I have a large plastic box ( the type that can be used on pick-up trucks or for storage). I want to know if it would be okay to keep my fish in there for a few days or could it be toxic for them?

Some plastics are treated with algicides, etc., so it's difficult to say for sure. If the manufacturer's name is on it, I'd give them a call. I'd recommend a trip to your local Farm and Fleet, and for a few bucks you can get a plastic tub used for livestock feeding/watering.

(Answer courtesy of Bryan Bateman).