On 18/06/2013 22:24, 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.

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.

Forget about things like soil, compost or even slow release pellets.
Get a liquid feed and just add a couple of drops to each pint of water
you use, remember the roots are in it all the time unlike pot plants
where the feed is "Diluted" by the compost.
At the end of the week you can tip the water onto any other plants you
may have growing in compost or soil, that way you wont be wasting any feed.
Remember if the feed is to strong you can easily kill the plant.
David @ what has been a sunny side of Swansea Bay this morning.