Wondering If Old Metal Waterer Worth Using

[12404914]

One of the waterers for my chickens broke and the backup isn't doing as well as it normally does. My dad has me trying to clean out an old rusty metal waterer. In the middle of trying, I wondered if it was even worth it considering how much stuff built up, probably from iron in the well water. I don't want to get my chickens sick because the waterer isn't safe to use. I plan to try to remove most of the rust and buildup. I'm posting photos and some details, if anything looks like a deal breaker please let me know so I can just try to get a new waterer.
Details:

• The chickens seem to not mind the taste. Before I started cleaning some water was poured in and the chickens started drinking despite other water being nearby. I quickly emptied it.
• It smells sort of like cooked mushrooms, but not in an appetizing way.
• I have no idea what the black staining is. I think the orange and red is rust.
• I'm worried dangerous algae or excess zinc has built up.
• The photos were taken after some vigorous scrubbing, some convex bumps/buildups of rust were present beforehand.

Thanks for any help!

 

[SmiYa0126]

That doesn't look good to me, I wouldn't use it.

 

[Gax000]

I don’t see anything that would hurt your chickens. Personally, I would use it but would replace it when something better goes on sale or becomes available.

 

[Ridgerunner]

My concern with that would be more with "will it still work" and not with "will it harm the chickens". That red is rust. I'm not sure what that black is, probably metal that has been deposited by some type of electrolysis when it was wet. It was coated with zinc to start with to help protect against corrosion but that was a long time ago. After basic cleaning to get the loose stuff off the water is not going to absorb enough metal from the zinc or iron to harm the chickens. Do not add vinegar or other acid to the water. Any acid like vinegar will speed up corrosion.

I'd use a wire brush or steel wool to remove the loose stuff. Maybe a scraper if some of that build up is loose and easily comes off. Then wash it with soap and water, then rinse the soap off well. Then use it.