Watercress in water tank?

We have a really big steel water tank (collects rain water from roof)...it gets a turnover of rain in/water out as we use it to water plants in the garden. Is this ok for growing water cress in?

 

I would say it will be ok to grow the water cress in, just don't eat it.

 

?? Would it not be safe to eat?

 

I would say not because it has been grown in a small tank which has a high metal concentrate. But that's just my opinion.
It may be that in the short term its fine (probably is) but if you grow and eat, grow and eat etc, that will be when you will be eating more metal than you should.

Like most things, too much of it does you harm, but i have no idea what eating metal from an old water tank will do to you.

 

Thanks for that. I will be cautious and not do it, I'd assumed as water tanks/troughs for animals it would be safe.

 

As I understand it Murdo, watercress is usually grown in moving water, i.e. stream beds, so although you draw water from the tank, much of the time it is not moving. Caution sounds the best option. :thumb: