On Wednesday, June 19, 2013 11:31:59 AM UTC+1, Jim Stone wrote:
wrote in message
...
On Tuesday, June 18, 2013 10:24:47 PM UTC+1, Jim Stone wrote:

Have a plant which i keep in water in a vase and change the water every
week. Its been happy like that for a long time. The roots are like onion
roots thick white strands.
Recently the leaves are becoming a bit pale, so I guess its short of a
nutrient or two.
A long time ago i heard that putting a copper coin in the water helps to
provide nutrients. True or not i don't know.

Copper isnt a useful nutrient for plants

Are there any other simple things you know of, that i could put in the
water
that would provide nutrients and still allow to me to change the water
easily each week? Thanks.

plant food, compost.
NT
----------------------------------------------------------------------Thanks.
I should have explained more carefully about when i said: allow me to change
the water *easily*. Since i put in fresh water every week, it would mean
messing about with adding new food or more compost each week.
I thought if there was some form of solid type nutrient with a slow release,
i could just tip away the water and then leave the nutrient items in the
vase and just replace the water, without it being a messy business. Thanks.

Plant food & compost are the only realistic options.